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NULL Value in Oracle Database | Oracle Tutorials for Beginners
 
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NULL Value in Oracle Database | Oracle Tutorials for Beginners NULL Value in Oracle Database NULL Value in Oracle SQL NULL Value in SQL NULL Value in Oracle Database Oracle Tutorials for Beginners Oracle Tutorials for Beginners Oracle PL/SQL Tutorials for Beginners Oracle PL/SQL Tutorials for Beginners Oracle PL/SQL Tutorials for Beginners how to select null values in oracle oracle compare null values in where clause null=null in oracle how to handle null in case statement in oracle how to check null value in oracle stored procedure oracle nvl null value in oracle query how to check empty column value in oracle how to select null values in oracle oracle is null vs = null oracle nvl oracle is not null oracle decode oracle isnull oracle case when null select null from table in oracle oracle compare null values in where clause oracle select null how to check empty column value in oracle oracle sql not null or empty oracle is not null how to handle null in case statement in oracle oracle isnull oracle nvl
Views: 457 Oracle PL/SQL World
SQL Null or Empty   How to Check for Null or Empty Column in SQL Server   SQL Training Online
 
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http://www.sqltrainingonline.com SQL Null or Empty - How to Check for Null or Empty Column in SQL Server - SQL Training Online You can download the sample table script at http://www.sqltrainingonline.com/how-to-filter-for-sql-null-or-empty-string/. In this video, I show you how to filter for a SQL null or empty string. It can be difficult to filter a null because you can't simply compare with an equal sign. You have to use a special IS NULL clause to make the filter work. I also show you how to combine both the SQL Null and Empty String together in a special trick with the isnull SQL Server function. I use SQL Server 2012 to demonstrate the technique. Let me know what you think by commenting or sharing on twitter, facebook, google+, etc. If you enjoy the video, please give it a like, comment, or subscribe to my channel. You can visit me at any of the following: SQL Training Online: http://www.sqltrainingonline.com Twitter: http://www.twitter.com/sql_by_joey Google+: https://plus.google.com/#100925239624117719658/posts LinkedIn: http://www.linkedin.com/in/joeyblue Facebook: http://www.facebook.com/sqltrainingonline
Views: 16437 Joey Blue
ORACLE SQL AND PL/SQL INTERVIEW QUESTION : SUBQUERY WITH NULL / NOT IN / NOT EXISTS OR OUTER JOIN
 
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This video demonstrates the oracle sql interview question where one need to use either not in, not exists or an outer join to get the desired result. For example if one is asked to fetch records from department table where department_id is not present in employee table
Views: 1874 Kishan Mashru
26. IS NULL and IS NOT NULL in SQL (Hindi)
 
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Please Subscribe Channel Like, Share and Comment Visit : www.geekyshows.com
Views: 18493 Geeky Shows
SQL Tutorial in Oracle - 4 NULL, LIKE, DISTINCT, ORDER BY
 
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SQL SELECT statement is used to fetch the data from a database table which returns data in the form of result table. These result tables are called result-sets. The LIKE operator is used in a WHERE clause to search for a specified pattern in a column. In SQL, wildcard characters are used with the SQL LIKE operator. SQL wildcards are used to search for data within a table. With SQL, the wildcards are: Wildcard Description % A substitute for zero or more characters _ A substitute for a single character [charlist] Sets and ranges of characters to match [^charlist] or [!charlist] Matches only a character NOT specified within the brackets Check out our website: http://www.telusko.com Follow Telusko on Twitter: https://twitter.com/navinreddy20 Follow on Facebook: Telusko : https://www.facebook.com/teluskolearnings Navin Reddy : https://www.facebook.com/navintelusko Follow Navin Reddy on Instagram: https://www.instagram.com/navinreddy20 Subscribe to our other channel: Navin Reddy : https://www.youtube.com/channel/UCxmkk8bMSOF-UBF43z-pdGQ?sub_confirmation=1 Telusko Hindi : https://www.youtube.com/channel/UCitzw4ROeTVGRRLnCPws-cw?sub_confirmation=1
Views: 17087 Telusko
Oracle SQL Tutorial 19 - ON DELETE (SET NULL and CASCADE)
 
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Welcome everyone! Something you need to consider when you are creating foreign keys is what happens if you delete the parent? As a reminder, the parent is the row that has the value you are referencing in the row that has a foreign key. Why is this something important to consider? It's important because foreign keys need to protect us from two primary things, unacceptable INSERT statements, and unacceptable DELETE statements. Let's see what happens when we try to insert incorrect data into the table with the foreign key: INSERT INTO projects VALUES (1, 'Update website homepage', 'CalebCurry') The response tells us plainly that there is no such user in the users table. So this works correctly. Deleting data on the other hand works a bit differently because the database does not know what you want to do with the child row when you delete the parent from the parent table. By default, we will get an error message that prevents the parent from being deleted, but there are some other options. How do we configure this? This is where the ON DELETE statement comes in. We add the keywords ON DELETE right after the foreign key and then we can give it the option of CASCADE or SET NULL. CASCADE means that if we delete the parent, we are also going to delete the child. In our situation what that means is that if somebody creates a project in our project table and then that persons account gets deleted, all of the projects he owns will also be deleted. CASCADE: CREATE TABLE projects( project_id NUMBER, Project_name VARCHAR2(50 CHAR) UNIQUE, creator VARCHAR2(50 CHAR) NOT NULL, CONSTRAINT projects_pk PRIMARY KEY (project_id), CONSTRAINT projects_users_fk FOREIGN KEY (creator) REFERENCES users (username) ON DELETE CASCADE ) SET NULL will take the value in the child table and get rid of it. What you are left with is NULL. This means that we have an orphaned child. The first thought you might have is that it is a bad thing to have an orphaned child, but in databases that is not always so. In our application if we had it set to SET NULL, when a user account gets deleted the projects would remain in existence they would just lack a creator. This might be a good thing if you are concerned about the long term survival of a project, this might be the route you want to go. It ultimately depends on the application purpose. If you don't like CASCADE or SET NULL, you can leave the entire ON DELETE statement and just have Oracle throw an error when a parent is deleted. As for us, we are going to use ON DELETE CASCADE. We need to use this with extreme caution. If you are not careful, someday you will run a delete a row and that will cascade through you database deleting a bunch of stuff you didn't want to delete. Stuff happens, so make sure you back up your database every once in eternity. Now, in the last video we started with a database design that had three tables. We've only created two in this video. In the next video we are going to create the next one, which is a little special. Then we'll finish things up by adding some indexes. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Support me on Patreon! http://www.patreon.com/calebcurry Subscribe to my newsletter: http://bit.ly/JoinCCNewsletter Donate!: http://bit.ly/DonateCTVM2. ~~~~~~~~~~~~~~~Additional Links~~~~~~~~~~~~~~~ More content: http://CalebCurry.com Facebook: http://www.facebook.com/CalebTheVideoMaker Google+: https://plus.google.com/+CalebTheVideoMaker2 Twitter: http://twitter.com/calebCurry Amazing Web Hosting - http://bit.ly/ccbluehost (The best web hosting for a cheap price!)
Views: 14314 Caleb Curry
Part 4   Delete duplicate rows in sql
 
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Link for all dot net and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/playlists Link for slides, code samples and text version of the video http://csharp-video-tutorials.blogspot.com/2014/05/part-4-delete-duplicate-rows-in-sql.html In this video, we will discuss deleting all duplicate rows except one from a sql server table. SQL Script to create Employees table Create table Employees ( ID int, FirstName nvarchar(50), LastName nvarchar(50), Gender nvarchar(50), Salary int ) GO Insert into Employees values (1, 'Mark', 'Hastings', 'Male', 60000) Insert into Employees values (1, 'Mark', 'Hastings', 'Male', 60000) Insert into Employees values (1, 'Mark', 'Hastings', 'Male', 60000) Insert into Employees values (2, 'Mary', 'Lambeth', 'Female', 30000) Insert into Employees values (2, 'Mary', 'Lambeth', 'Female', 30000) Insert into Employees values (3, 'Ben', 'Hoskins', 'Male', 70000) Insert into Employees values (3, 'Ben', 'Hoskins', 'Male', 70000) Insert into Employees values (3, 'Ben', 'Hoskins', 'Male', 70000) The delete query should delete all duplicate rows except one. Here is the SQL query that does the job. PARTITION BY divides the query result set into partitions. WITH EmployeesCTE AS ( SELECT *, ROW_NUMBER()OVER(PARTITION BY ID ORDER BY ID) AS RowNumber FROM Employees ) DELETE FROM EmployeesCTE WHERE RowNumber ] 1
Views: 321787 kudvenkat
09 of 15 SQL Basics with Oracle - Using IN, NOT IN, NULL and NOT NULL
 
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This video shows how to use the IN clause as an alternative to using the OR operators. The IN clause is more compact--it's easier to type and read than multiple OR criteria. Examples of checking for NULL and NOT NUL are also given. (9 of 15) There is also an "Advanced SQL" series. (Search for "databasemec" for tutorials using SQL Server.)
Views: 2948 Jennifer Kreie
SQL Server Select NULL value or IS NOT Queries Command DB
 
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SQL Server Database Select NULL value or IS NOT Queries Command DB.
Views: 35 Saidah Faulia
IS NOT NULL, IS NULL, NVL FUNCTION in oracle sql
 
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Oracle sql tutorial, How to select, retrieve rows with null values, not null values and NVL function in oracle SQL
Learn How to Use INSERT INTO SELECT Statement in SQL
 
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Learn about using INSERT INTO SELECT statement. In SQL we can copy the data rows from one table to another table. The INSERT INTO SELECT statement copies the data rows from one table and inserts into an existing table. Both actions are executed in a single SQL statement. The source table and target table must have similar table definition that is the same columns with same data types. Any existing data rows or records in target table remain unaffected. Here are the examples showing use of INSERT INTO SELECT statements, "INSERT INTO targetTable SELECT * FROM sourceTable;" "INSERT INTO targetTable (column1, column2) SELECT column1, column2 FROM sourceTable;" We can copy all columns or specified columns from source table to target table. Select the "school" database, "USE school;" First, lets create a new students table which will act as as target table to store the data rows. "CREATE TABLE students2 ( studentid INT PRIMARY KEY AUTO_INCREMENT, firstname VARCHAR(40) NOT NULL, lastname VARCHAR(40) NOT NULL, class VARCHAR(20), age INT );" Hit enter to create the table. Lets populate the 'students2' table from source table 'students' using INSERT INTO SELECT statement. The SQL statement will be, "INSERT INTO students2 SELECT * FROM students;" Lets get the data rows from 'students2' table, "SELECT * FROM students2;" And we have data rows in our new 'students2' table. Check out the whole playlist of SQL Tutorials or Individual video from the following links, SQL Tutorial for Beginners. Introduction to SQL Basics https://www.youtube.com/playlist?list=PLhwzZMYRiUErXXX0Ryud2R7RjesCEdTqi 1.Learn What is SQL? Introduction to SQL https://www.youtube.com/watch?v=ox6zUOKascs 2.Learn How to Install MySQL Database Server on Windows Operating System https://www.youtube.com/watch?v=vtnoWaydkEU 3.Learn What is Database? How to Create and Show Databases using SQL https://www.youtube.com/watch?v=-yJgWq6K_U8 4.Learn How to Select and Use Existing Database using SQL https://www.youtube.com/watch?v=QMViQ38SPxc 5.Learn How to Delete or Remove Database using SQL https://www.youtube.com/watch?v=wjEOZKvfH4c 6.Learn What is Database Table? How to Create a Database Table using SQL? https://www.youtube.com/watch?v=8SvtNIfzC4o 7.Learn How to Modify or Update Database Table using SQL https://www.youtube.com/watch?v=1he5oZzG33o 8.Learn How to Delete or Remove Database Table using SQL https://www.youtube.com/watch?v=JD87WvBist0 9.Learn How to Add Data Rows in a Table using SQL https://www.youtube.com/watch?v=UB-bQxAQbWg 10.Learn How to Use INSERT INTO SELECT Statement in SQL https://www.youtube.com/watch?v=U4ApxHF4R1g 11.Learn How to Update Data Rows using Update Statement in SQL https://www.youtube.com/watch?v=lE1BmNbFJdo 12.Learn How to Delete Data Rows using Delete Statement in SQL https://www.youtube.com/watch?v=1ViqX1tFgYM Subscribe to my channel: https://www.youtube.com/channel/UCvrq9OowoORTV5Gs_jpADhw
SQL tutorial 73: NVL2 SQL null function By Manish Sharma RebellionRider
 
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Part 2: SQL Null Function NVL2 learn the concepts of NVL null function in this tutorial with examples and all the Interview concepts covered ------------------------------------------------------------------------ ►►►LINKS◄◄◄ Blog : http://bit.ly/nvl2-null-function Previous Tutorial ► NVL function https://youtu.be/aRoTR5Jn6K0 ------------------------------------------------------------------------- ►►►Let's Get Free Uber Cab◄◄◄ Use Referral Code UberRebellionRider and get $20 free for your first ride. ------------------------------------------------------------------------- ►►►Help Me In Getting A Job◄◄◄ ►Help Me In Getting A Good Job By Connecting With Me on My LinkedIn and Endorsing My Skills. All My Contact Info is Down Below. You Can Also Refer Me To Your Company Thanks ------------------------------------------------------------------------- Copy Cloud referral link || Use this link to join copy cloud and get 20GB of free storage https://copy.com?r=kb4rc1 -------------------------------------------------------------------------- ►Make sure you SUBSCRIBE and be the 1st one to see my videos! -------------------------------------------------------------------------- Amazon Wishlist: http://bit.ly/wishlist-amazon ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ►►►Find me on Social Media◄◄◄ Follow What I am up to as it happens on https://twitter.com/rebellionrider https://www.facebook.com/imthebhardwaj http://instagram.com/rebellionrider https://plus.google.com/+Rebellionrider http://in.linkedin.com/in/mannbhardwaj/ http://rebellionrider.tumblr.com/ http://www.pinterest.com/rebellionrider/ You can also Email me at for E-mail address please check About section Please please LIKE and SHARE my videos it makes me happy. Thanks for liking, commenting, sharing and watching more of our videos This is Manish from RebellionRider.com ♥ I LOVE ALL MY VIEWERS AND SUBSCRIBERS
Views: 21003 Manish Sharma
Oracle SQL Lecture 28: IS NULL and IS NOT NULL
 
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Oracle SQL: IS NULL and IS NOT NULL https://www.youtube.com/channel/UCnBpiBIOtRgMsk4G7Ri1jbQ
Views: 717 Oracle SQL
How to add Hard Disks in Oracle VirtualBox
 
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We will learn how to add hard disks into an existing virtual machines. This is identical to adding hard disks to a physical machine and can be used for a variety of reasons: more data storage, better performance or increased reliability via RAID setup and others. Dynamic Storage Terms: http://www.avoiderrors.net/?p=4034
Views: 37668 AvoidErrors
Different ways to replace NULL in sql server - Part 15
 
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In this video we will learn about the different ways to replace NULL values in sql server. 1. ISNULL() function 2. CASE statement 3. COALESCE() function Text version of the video http://csharp-video-tutorials.blogspot.com/2012/08/different-ways-to-replace-null-in-sql.html Slides http://csharp-video-tutorials.blogspot.com/2013/08/part-15-different-ways-to-replace-null.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 262951 kudvenkat
Oracle SQL Tutorial 10 - Whitespace, Case Sensitivity, and Comments
 
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SELECT "Hello World" FROM DUAL The first thing you should know about writing queries is that this SQL is not whitespace sensitive. That means we can space this out however we wish. The only requirement is that you do not separate keywords out with spaces. They must be as one entity. Another gotcha is that when you are inside of quotes, whitespace becomes very important. That means if inside of a string you put a character and then 10 spaces, every single one of those spaces is going to part of that string: SELECT "Hello World" FROM DUAL The next thing you should notice is the capitalization. When we type SQL, by convention we capitalize all keywords. I personally really like this because you can easily see the difference between keywords and words that we created or use. But obviously we could capitalize the letters in the quotes. Keep in mind that this is a convention, meaning you do not have to follow this. Oracle is also case insensitive in that SELECT and select both do the same thing. Strings, once again, care about casing. Take this, for example: SELECT 'true' FROM DUALWHERE 'Hello' = 'Hello' And compare the results to this: SELECT 'true' FROM DUALWHERE 'Hello' = 'hello' Only the first one outputs the value true. Once we get into creating database objects such as tables with columns, those are not case sensitive either. That means instead of selecting from DUAL, you can select from DuAl Finally, I shall introduce you to comments. Comments allow you to tell the database engine that you want it to ignore a certain part of your code and not execute it. This is helpful if you want to document your code. It is also useful if you want to have multiple SQL statements open in one tab, but don't want to hover over the one you want to execute. You can comment out the ones you are not using and uncomment them when you are done. Using – will comment out the rest of the line, Using /* */ will comment everything between. This can even be used over multiple lines. But now, let's move onto the important stuff… CREATING TABLES!!!!! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ HELP ME! http://www.patreon.com/calebcurry Subscribe to my newsletter: http://bit.ly/JoinCCNewsletter Donate!: http://bit.ly/DonateCTVM2. ~~~~~~~~~~~~~~~Additional Links~~~~~~~~~~~~~~~ More content: http://CalebCurry.com Facebook: http://www.facebook.com/CalebTheVideoMaker Google+: https://plus.google.com/+CalebTheVideoMaker2 Twitter: http://twitter.com/calebCurry Amazing Web Hosting - http://bit.ly/ccbluehost (The best web hosting for a cheap price!)
Views: 15327 Caleb Curry
Conditional Operators in Oracle Database | Oracle Tutorials for Beginners
 
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Conditional Operators in Oracle Database | Oracle Tutorials for Beginners Oracle Tutorials for Beginners Conditional Operators in Oracle Database Conditional Operators in Oracle Database Conditional Operators in Oracle SQL Greater than, Less than in Oracle Equal to in Oracle Not Equal to Operator in Oracle conditional operator in oracle conditional operator in oracle conditional operator in oracle Oracle Conditional Operators
Views: 272 Oracle PL/SQL World
SQL Tutorial - 13: Inserting Data Into a Table From Another Table
 
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In this tutorial we'll learn to use the INSERT Query to copy data from one table into another.
Views: 241782 The Bad Tutorials
Oracle Table Creation Inserting Records Null Values 1
 
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Create new connection with new user in Oracle SQL Developer
 
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This video shows you how to create a new connection using a new user account (other than the system user account) in Oracle SQL Developer, so that you have a clean workspace without all the clutter of system tables. It is NOT a general introduction to using Oracle SQL Developer.
Views: 335692 Chitu Okoli
NOT NULL Constraint in Oracle Database
 
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NOT NULL Constraint in Oracle Database
SQL Server 30 - How to INSERT Data
 
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Now that we have our tables created, we need to learn how to actually put data into our tables. That is where the INSERT command comes in. The basic syntax looks like: INSERT INTO TableName VALUES(data…); Data is where we put a value for each column. Strings are single quoted, numbers are left blank with no quotes. Just like when we create tables we try to create the parent tables first, we do the same with inserting data. We always want to insert the parent rows first. So let's add a species to our table. As a reminder, this is what our CREATE TABLE looks like: CREATE TABLE Species( ID INT PRIMARY KEY IDENTITY, Species VARCHAR(50) NOT NULL UNIQUE, FriendlyName VARCHAR(50) NOT NULL ); Now to insert data: INSERT INTO Species VALUES('Pentalagus P. furnessi', 'Bunny'); Now you can see that there may a violation of everything being atomic because we are actually storing the genus and species of this animal in one column. But…YOLO. Now we can view this data by finding the table in the object explorer, right clicking, and selecting Edit Top 200 Rows. Notice that the IDENTITY column is automatically filled. Now, this is a great time to show you some stuff regarding foreign keys. The first thing I want to show you is how they protect our data integrity. Let's insert some data in the Animals table and try to reference an invalid species. Once again, here is what our table creation looks like: CREATE TABLE Animals( ID INT PRIMARY KEY IDENTITY, Name VARCHAR(50) NOT NULL, Species INT NOT NULL REFERENCES Species(ID), ContactEmail VARCHAR(50) NOT NULL UNIQUE ); INSERT INTO Animals VALUES('Sally', 2, '[email protected]'); SQL Server does not let us insert this data. The second thing I wanted to show you is that the name of the constraint that is in violation is being shown here. That is why naming your constraints can come in handy so when this happens you can find it much easier. Last thing is that if you want to INSERT multiple rows, throw a comma after the VALUES, and put another parenthesis with more data: INSERT INTO Animals VALUES('Sally', 1', '[email protected]'), ('Franklin', 1, '[email protected]') ; Maybe someday we will get around to adding a row to our species table for turtles, but for now we are going to make Franklin a bunny. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Support me! http://www.patreon.com/calebcurry Subscribe to my newsletter: http://bit.ly/JoinCCNewsletter Donate!: http://bit.ly/DonateCTVM2. ~~~~~~~~~~~~~~~Additional Links~~~~~~~~~~~~~~~ More content: http://CalebCurry.com Facebook: http://www.facebook.com/CalebTheVideoMaker Google+: https://plus.google.com/+CalebTheVideoMaker2 Twitter: http://twitter.com/calebCurry Amazing Web Hosting - http://bit.ly/ccbluehost (The best web hosting for a cheap price!)
Views: 3431 Caleb Curry
MySQL for Beginners 006: Null Values and Not Null
 
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This is a free section of a full course to get you started with MySQL. Full course: http://courses.caveofprogramming.com/courses/mysql-and-sql-for-beginners MySQL allows columns to take "null" (not specified) values by default, so we'd better take a look ...
Views: 2884 Cave of Programming
Subqueries in sql   Part 59
 
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In this video we will discuss about subqueries in sql server. Let us understand subqueris with an example. Please create the required tables and insert sample data using the script below. Create Table tblProducts ( [Id] int identity primary key, [Name] nvarchar(50), [Description] nvarchar(250) ) Create Table tblProductSales ( Id int primary key identity, ProductId int foreign key references tblProducts(Id), UnitPrice int, QuantitySold int ) Insert into tblProducts values ('TV', '52 inch black color LCD TV') Insert into tblProducts values ('Laptop', 'Very thin black color acer laptop') Insert into tblProducts values ('Desktop', 'HP high performance desktop') Insert into tblProductSales values(3, 450, 5) Insert into tblProductSales values(2, 250, 7) Insert into tblProductSales values(3, 450, 4) Insert into tblProductSales values(3, 450, 9) Write a query to retrieve products that are not at all sold? This can be very easily achieved using subquery as shown below. Select [Id], [Name], [Description] from tblProducts where Id not in (Select Distinct ProductId from tblProductSales) Most of the times subqueries can be very easily replaced with joins. The above query is rewritten using joins and produces the same results. Select tblProducts.[Id], [Name], [Description] from tblProducts left join tblProductSales on tblProducts.Id = tblProductSales.ProductId where tblProductSales.ProductId IS NULL In this example, we have seen how to use a subquery in the where clause. Let us now discuss about using a sub query in the SELECT clause. Write a query to retrieve the NAME and TOTALQUANTITY sold, using a subquery. Select [Name], (Select SUM(QuantitySold) from tblProductSales where ProductId = tblProducts.Id) as TotalQuantity from tblProducts order by Name Query with an equivalent join that produces the same result. Select [Name], SUM(QuantitySold) as TotalQuantity from tblProducts left join tblProductSales on tblProducts.Id = tblProductSales.ProductId group by [Name] order by Name From these examples, it should be very clear that, a subquery is simply a select statement, that returns a single value and can be nested inside a SELECT, UPDATE, INSERT, or DELETE statement. It is also possible to nest a subquery inside another subquery. According to MSDN, subqueries can be nested upto 32 levels. Subqueries are always encolsed in paranthesis and are also called as inner queries, and the query containing the subquery is called as outer query. The columns from a table that is present only inside a subquery, cannot be used in the SELECT list of the outer query. Next Video: What to choose for performance? Queries that involve a subquery or a join Text version of the video http://csharp-video-tutorials.blogspot.com/2013/01/subqueries-in-sql-part-59.html Slides http://csharp-video-tutorials.blogspot.com/2013/09/part-59-subqueries-in-sql-server.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists
Views: 199851 kudvenkat
COALESCE Function in SQL ORACLE Query With Example
 
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ORACLE/PLSQL: COALESCE FUNCTION The Oracle/PLSQL COALESCE function returns the first non-null expression in the list. If all expressions evaluate to null, then the COALESCE function will return null. The syntax for the Oracle/PLSQL COALESCE function is: coalesce( expr1, expr2, ... expr_n ) PARAMETERS: expr1 to expr_n are the expressions to test for non-null values. EXAMPLE: The COALESCE function can be used in Oracle/PLSQL. You could use the coalesce function in a SQL statement as follows: SELECT COALESCE( address1, address2, address3 ) result FROM suppliers; The above COALESCE function is equivalent to the following IF-THEN-ELSE statement: IF address1 is not null THEN result := address1; ELSIF address2 is not null THEN result := address2; ELSIF address3 is not null THEN result := address3; ELSE result := null; END IF; The COALESCE function will compare each value, one by one. Lets apply the same to emp table. We have some NULL values in comm and mgr columns. but not in any other columns. So lets take a example for this 2 columns. COALESCE(comm,mgr,sal) Here if comm is null, function returns mgr value. If mgr is null it returns sal value! Query used in video: SELECT ename,comm,mgr,sal,COALESCE(comm,mgr,sal) result FROM emp;
Views: 6255 WingsOfTechnology
Dynamic SQL in Stored Procedure
 
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In this video we will discuss, using dynamic sql in a stored procedure and it's implications from sql injection perspective. We will discuss performance implications of using dynamic sql in a stored procedure in a later video. Text version of the video http://csharp-video-tutorials.blogspot.com/2017/04/dynamic-sql-in-stored-procedure.html Slides http://csharp-video-tutorials.blogspot.com/2017/04/dynamic-sql-in-stored-procedure_11.html All SQL Server Text Articles http://csharp-video-tutorials.blogspot.com/p/free-sql-server-video-tutorials-for.html All SQL Server Slides http://csharp-video-tutorials.blogspot.com/p/sql-server.html All SQL Server Tutorial Videos https://www.youtube.com/playlist?list=PL08903FB7ACA1C2FB All Dot Net and SQL Server Tutorials in English https://www.youtube.com/user/kudvenkat/playlists?view=1&sort=dd All Dot Net and SQL Server Tutorials in Arabic https://www.youtube.com/c/KudvenkatArabic/playlists Consider the following stored procedure "spSearchEmployees". We implemented this procedure in Part 139 of SQL Server tutorial. This stored procedure does not have any dynamic sql in it. It is all static sql and is immune to sql injection. Create Procedure spSearchEmployees @FirstName nvarchar(100) = NULL, @LastName nvarchar(100) = NULL, @Gender nvarchar(50) = NULL, @Salary int = NULL As Begin Select * from Employees where (FirstName = @FirstName OR @FirstName IS NULL) AND (LastName = @LastName OR @LastName IS NULL) AND (Gender = @Gender OR @Gender IS NULL) AND (Salary = @Salary OR @Salary IS NULL) End Go Whether you are creating your dynamic sql queries in a client application like ASP.NET web application or in a stored procedure, you should never ever concatenate user input values. Instead you should be using parameters. Notice in the following example, we are creating dynamic sql queries by concatenating parameter values, instead of using parameterized queries. This stored procedure is prone to SQL injection. Let's prove this by creating a "Search Page" that calls this procedure. Create Procedure spSearchEmployeesBadDynamicSQL @FirstName nvarchar(100) = NULL, @LastName nvarchar(100) = NULL, @Gender nvarchar(50) = NULL, @Salary int = NULL As Begin Declare @sql nvarchar(max) Set @sql = 'Select * from Employees where 1 = 1' if(@FirstName is not null) Set @sql = @sql + ' and FirstName=''' + @FirstName + '''' if(@LastName is not null) Set @sql = @sql + ' and LastName=''' + @LastName + '''' if(@Gender is not null) Set @sql = @sql + ' and Gender=''' + @Gender + '''' if(@Salary is not null) Set @sql = @sql + ' and Salary=''' + @Salary + '''' Execute sp_executesql @sql End Go Add a Web Page to the project that we have been working with in our previous video. Name it "DynamicSQLInStoredProcedure.aspx". Copy and paste the HTML and code available on my blog at the following link http://csharp-video-tutorials.blogspot.com/2017/04/dynamic-sql-in-stored-procedure.html At this point, run the application and type the following text in the "Firsname" text and click "Search" button. Notice "SalesDB" database is dropped. Our application is prone to SQL injection as we have implemented dynamic sql in our stored procedure by concatenating strings instead of using parameters. ' Drop database SalesDB -- In the following stored procedure we have implemented dynamic sql by using parameters, so this is not prone to sql injecttion. This is an example for good dynamic sql implementation. Create Procedure spSearchEmployeesGoodDynamicSQL @FirstName nvarchar(100) = NULL, @LastName nvarchar(100) = NULL, @Gender nvarchar(50) = NULL, @Salary int = NULL As Begin Declare @sql nvarchar(max) Declare @sqlParams nvarchar(max) Set @sql = 'Select * from Employees where 1 = 1' if(@FirstName is not null) Set @sql = @sql + ' and [email protected]' if(@LastName is not null) Set @sql = @sql + ' and [email protected]' if(@Gender is not null) Set @sql = @sql + ' and [email protected]' if(@Salary is not null) Set @sql = @sql + ' and [email protected]' Execute sp_executesql @sql, N'@FN nvarchar(50), @LN nvarchar(50), @Gen nvarchar(50), @sal int', @[email protected], @[email protected], @[email protected], @[email protected] End Go On the code-behind page, use stored procedure spSearchEmployeesGoodDynamicSQL instead of spSearchEmployeesBadDynamicSQL. We do not have to change any other code. At this point run the application one more time and type the following text in the "Firstname" textbox and click the "Search" button. ' Drop database SalesDB -- Notice "SalesDB" database is not dropped, So in this case our application is not succeptible to SQL injection attack. Summary : Whether you are creating dynamic sql in a client application (like a web application) or in a stored procedure always use parameters instead of concatnating strings. Using parameters to create dynamic sql statements prevents sql injection.
Views: 29400 kudvenkat
SQL 011 SELECT NULL or What if the column value is unknown?
 
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Explains NULL or What if the column value is unknown? From http://computerbasedtraininginc.com SQL Course. Learn by doing SQL commands for ANSI Standard SQL, Access, DB2, MySQL, Oracle, PostgreSQL, and SQL Server.
Views: 1576 cbtinc
SQL 018 SELECT WHERE IS NULL or How can I find unknown values?
 
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Explains the SELECT WHERE IS NULL clause. From http://ComputerBasedTrainingInc.com SQL Course. Learn by doing SQL commands for ANSI Standard SQL, Access, DB2, MySQL, Oracle, PostgreSQL, and SQL Server.
Views: 977 cbtinc
Null: Databases for Developers #10
 
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The null value represents missing or unknown information. But using it brings complications to your SQL. In this video Chris discusses how to work with null to ensure you get the correct results. Further reading: Oracle Database SQL Reference on Nulls: http://docs.oracle.com/database/122/SQLRF/Nulls.htm#SQLRF30037 Null related functions: http://docs.oracle.com/database/122/SQLRF/Single-Row-Functions.htm#SQLRF51187 Is null condition: http://docs.oracle.com/database/122/SQLRF/Null-Conditions.htm#SQLRF52152 Need help with SQL? Ask us over on AskTOM: https://asktom.oracle.com Twitter: https://twitter.com/ChrisRSaxon Daily SQL Twitter tips: https://twitter.com/SQLDaily All Things SQL blog: https://blogs.oracle.com/sql/ ============================ The Magic of SQL with Chris Saxon Copyright © 2015 Oracle and/or its affiliates. Oracle is a registered trademark of Oracle and/or its affiliates. All rights reserved. Other names may be registered trademarks of their respective owners. Oracle disclaims any warranties or representations as to the accuracy or completeness of this recording, demonstration, and/or written materials (the “Materials”). The Materials are provided “as is” without any warranty of any kind, either express or implied, including without limitation warranties or merchantability, fitness for a particular purpose, and non-infringement.
Views: 2587 The Magic of SQL
NULL-Related Functions in Oracle
 
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An overview of some of the functions Oracle provides to handle NULL values in SQL and PL/SQL. For more information see: https://oracle-base.com/articles/misc/null-related-functions Website: https://oracle-base.com Blog: https://oracle-base.com/blog Twitter: https://twitter.com/oraclebase Cameo by Bjoern Rost Blog: http://portrix-systems.de/blog/brost/ Twitter: https://twitter.com/brost Cameo appearances are for fun, not an endorsement of the content of this video.
Views: 2582 ORACLE-BASE.com
Structured Query Language Tutorial SQL Part 23   NOT NULL Constraint Command Prompt   CMD
 
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Structured Query Language Tutorial SQL Part 23 NOT NULL Constraint Command Prompt CMD
Views: 44 Maurice Muteti
SQL Tip #4: Simple SQL Select Statement with IS NULL
 
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This example shows you how to create a SELECT statement using the IS NULL property in MS SQL Server. The typical syntax you may find would look like this: Select * from table where field IS NULL;
Views: 802 ITCorpsTV
Learn Oracle | PL SQL Loops
 
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Pebbles present, Learn Oracle 10g with Step By Step Video Tutorials. Learn Oracle 10g Tutorial series contains the following videos : Learn Oracle - History of Oracle Learn Oracle - What is Oracle - Why do we need Oracle Learn Oracle - What is a Database Learn Oracle - What is Grid Computing Learn Oracle - What is Normalization Learn Oracle - What is ORDBMS Learn Oracle - What is RDBMS Learn Oracle - Alias Names, Concatenation, Distinct Keyword Learn Oracle - Controlling and Managing User Access (Data Control Language) Learn Oracle - Introduction to SQL Learn Oracle - Oracle 10g New Data Types Learn Oracle - How to Alter a Table using SQL Learn Oracle - How to Create a Package in PL SQL Learn Oracle - How to Create a Report in SQL Plus Learn Oracle - How to Create a Table using SQL - Not Null, Unique Key, Primary Key Learn Oracle - How to Create a Table using SQL Learn Oracle - How to Create a Trigger in PL SQL Learn Oracle - How to Delete Data from a Table using SQL Learn Oracle - How to Drop and Truncate a Table using SQL Learn Oracle - How to Insert Data in a Table using SQL Learn Oracle - How to open ISQL Plus for the first time Learn Oracle - How to Open SQL Plus for the First Time Learn Oracle - How to Update a Table using SQL Learn Oracle - How to use Aggregate Functions in SQL Learn Oracle - How to use Functions in PL SQL Learn Oracle - How to use Group By, Having Clause in SQL Learn Oracle - How to Use Joins, Cross Join, Cartesian Product in SQL Learn Oracle - How to use Outer Joins (Left, Right, Full) in SQL Learn Oracle - How to use the Character Functions, Date Functions in SQL Learn Oracle - How to use the Merge Statement in SQL Learn Oracle - How to use the ORDER BY Clause with the Select Statement Learn Oracle - How to use the SELECT Statement Learn Oracle - How to use the Transactional Control Statements in SQL Learn Oracle - How to use PL SQL Learn Oracle - Data Types in PL SQL Learn Oracle - Exception Handling in PL SQL Learn Oracle - PL SQL Conditional Logics Learn Oracle - PL SQL Cursor Types - Explicit Cursor, Implicit Cursor Learn Oracle - PL SQL Loops Learn Oracle - Procedure Creation in PL SQL Learn Oracle - Select Statement with WHERE Cause Learn Oracle - SQL Operators and their Precedence Learn Oracle - Using Case Function, Decode Function in SQL Learn Oracle - Using Logical Operators in the WHERE Clause of the Select Statement Learn Oracle - Using Rollup Function, Cube Function Learn Oracle - Using Set Operators in SQL Learn Oracle - What are the Different SQL Data Types Learn Oracle - What are the different types of Databases Visit Pebbles Official Website - http://www.pebbles.in Subscribe to our Channel – https://www.youtube.com/channel/UCNNjWVsQqaMYccY044vtHJw?sub_confirmation=1 Engage with us on Facebook at https://www.facebook.com/PebblesChennai Please Like, Share, Comment & Subscribe
Views: 154 Pebbles Tutorials
SQL6 - NULL values; the COUNT function
 
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What NULL values are, using "IS NULL" and "IS NOT NULL" in where statements. The count function, including examples of using COUNT with a WHERE clause.
Views: 670 Charles Boisvert
Create, Alter, Drop Not Null constraint in SQL Server - Part 10
 
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Subscribe to IT PORT : https://www.youtube.com/c/itport28 SQL Server Tutorial in Tamil : https://www.youtube.com/playlist?list=PLouAaeZ4xQ64enJDwWVvN3KduuZRlUrb3 SQL Server Concepts in Tamil : https://www.youtube.com/playlist?list=PLouAaeZ4xQ67kdNIByJKAGBIBhor_h4Hs SQL Server Analytic Functions in Tamil : https://www.youtube.com/playlist?list=PLouAaeZ4xQ65XIU5azEUgLVrBKEl-jWMV SQL Server Tutorial : https://www.youtube.com/playlist?list=PLouAaeZ4xQ66AYrzPtxt2SeeR4UABcBcO SQL Server Concepts : https://www.youtube.com/playlist?list=PLouAaeZ4xQ66zRe8-nDDy-YHY2o0rmbn4 SQL Server Analytic Functions : https://www.youtube.com/playlist?list=PLouAaeZ4xQ64hTsEdhLsVBquE1vERWngX NULL is the term used to represent a missing value. A NULL value in a table is a value in a field that appears to be blank. A field with a NULL value is a field with no value. NULL value is different than a zero value or a field that contains spaces By default, a column can hold NULL values. The NOT NULL constraint enforces a column to NOT accept NULL values. This enforces a field to always contain a value, which means that you cannot insert a new record, or update a record without adding a value to this field
Views: 359 IT Port
Oracle SQL Video Tutorial 3 : NULL
 
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Oracle SQL Video Tutorials 3 : Null Values
Views: 1747 Just Channel
SQL Handling NULL
 
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Jamie King of Neumont University speaking on why NULL in SQL is different and how we compensate for it.
Views: 5715 Jamie King
How to find your sql server name (instance) for Management Studio
 
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This tutorial shows you how to find your server name or instance for connecting to SQL Management Studio (SSMS). Step by step tutorial on how to check if SQL is installed on your machine using the services to check that Microsoft SQL Server has been started. Next how to find your instance name using SQL Server Configuration Manager using SQL 2012 or 2014 folder. I show you how to connect to the instance name in the Connect to Server SQL Sever 2014 box. The Server Name is made up of the following: ServerName/Instance Name 1: To find the Server name type the following into command prompt: SQLCMD -L 2: To find the instance name go to Microsoft configuration manager there you will see your version of sql server in my case sql server express as such I know my instance name is sql server express 3. Put the server name and instance name together as per the video SOPHIA-HP/SQLEXPRESS To request a video: http://itsophy.com/request-video/ More SQL Server videos: http://www.youtube.com/playlist?list=PLrTXCzXE7TKKhIhGtl65lYMAHP6xN5Wa4 My Blog: http://itsophy.com/
Views: 119098 ITSophy
Reading SQL:  Null Values in a Subquery: SQL Tutorial 75
 
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Please watch: "Install Oracle Database 12c Release 2 on Windows 10 Professional 64 bit" https://www.youtube.com/watch?v=5705VFJmku0 -~-~~-~~~-~~-~- : SQL Tutorial
Views: 80 Solution Wizard
SQL Complete Tutorial - Combined search conditions for IN, OR, IS NULL, AND, NOT - Chapter 23
 
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In this video, I have explained the logical AND, OR, and NOT keywords and parentheses to group the search criteria.
Views: 391 Vicky's Blog
Part 1   How to find nth highest salary in sql
 
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Link for all dot net and sql server video tutorial playlists http://www.youtube.com/user/kudvenkat/playlists Link for slides, code samples and text version of the video http://csharp-video-tutorials.blogspot.com/2014/05/part-1-how-to-find-nth-highest-salary_17.html This is a very common SQL Server Interview Question. There are several ways of finding the nth highest salary. By the end of this video, we will be able to answer all the following questions as well. How to find nth highest salary in SQL Server using a Sub-Query How to find nth highest salary in SQL Server using a CTE How to find the 2nd, 3rd or 15th highest salary Let's use the following Employees table for this demo Use the following script to create Employees table Create table Employees ( ID int primary key identity, FirstName nvarchar(50), LastName nvarchar(50), Gender nvarchar(50), Salary int ) GO Insert into Employees values ('Ben', 'Hoskins', 'Male', 70000) Insert into Employees values ('Mark', 'Hastings', 'Male', 60000) Insert into Employees values ('Steve', 'Pound', 'Male', 45000) Insert into Employees values ('Ben', 'Hoskins', 'Male', 70000) Insert into Employees values ('Philip', 'Hastings', 'Male', 45000) Insert into Employees values ('Mary', 'Lambeth', 'Female', 30000) Insert into Employees values ('Valarie', 'Vikings', 'Female', 35000) Insert into Employees values ('John', 'Stanmore', 'Male', 80000) GO To find the highest salary it is straight forward. We can simply use the Max() function as shown below. Select Max(Salary) from Employees To get the second highest salary use a sub query along with Max() function as shown below. Select Max(Salary) from Employees where Salary [ (Select Max(Salary) from Employees) To find nth highest salary using Sub-Query SELECT TOP 1 SALARY FROM ( SELECT DISTINCT TOP N SALARY FROM EMPLOYEES ORDER BY SALARY DESC ) RESULT ORDER BY SALARY To find nth highest salary using CTE WITH RESULT AS ( SELECT SALARY, DENSE_RANK() OVER (ORDER BY SALARY DESC) AS DENSERANK FROM EMPLOYEES ) SELECT TOP 1 SALARY FROM RESULT WHERE DENSERANK = N To find 2nd highest salary we can use any of the above queries. Simple replace N with 2. Similarly, to find 3rd highest salary, simple replace N with 3. Please Note: On many of the websites, you may have seen that, the following query can be used to get the nth highest salary. The below query will only work if there are no duplicates. WITH RESULT AS ( SELECT SALARY, ROW_NUMBER() OVER (ORDER BY SALARY DESC) AS ROWNUMBER FROM EMPLOYEES ) SELECT SALARY FROM RESULT WHERE ROWNUMBER = 3
Views: 862298 kudvenkat
SQL TUTORIALS : NULL VALUES
 
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WHAT IS NULL IN SQL PLUS? DEFINING NULL VALUE.
Views: 2634 learnoracle9i
IS NULL SQL
 
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שימוש בשפת SQL IS NULL
Views: 113 Gidi Aviezer
SQL Server - Query Table Record Data via TSQL - SELECT ISNULL
 
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How to use the ISNULL() function in SQL Server to reset record fields with null values to something that is more workable. This tutorial also briefly covers concatenation with null values as well as the CAST() function.
Views: 246 Dave Merton
Oracle Database11g tutorials 12 || SQL Concat Function - SQL character manipulation function
 
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Link for SQL concat function: http://www.rebellionrider.com/SQL-concat-function.htm SQL Concat function/SQL concat() function First function of SQL character manipulation function. Two have in depth knowledge of SQL concatenation operator Please watch my video on SQL concatenation Operator http://youtu.be/PYMeFe72Bas Tool used in this tutorial is command prompt. This tutorial series is part of SQL expert exam certification training. if you are preparing for SQL certification you can use my tutorials. This SQL Tutorial is a part of free training. Copy Cloud referral link || Use this link to join copy cloud and get 20GB of free storage https://copy.com?r=j7eYO7 Link for SQL function introduction Video 10 http://youtu.be/5rx8Q4x4-qI Link SQL concat Article http://www.rebellionrider.com/SQL-concat-function.htm Contacts E-Mail [email protected] Twitter https://twitter.com/rebellionrider Instagram http://instagram.com/rebellionrider Facebook. https://www.facebook.com/imthebhardwaj Linkedin. in.linkedin.com/in/mannbhardwaj/ Thanks for linking, commenting, sharing and watching more of our videos This is Manish from RebellionRider.com -------------------------------------------------------------------------------------------- SQL Concat () function is a Character manipulation function which is a category of SQL character function. We have already discussed the intro of SQL character function in Video 10. You can find link of this video in description below. Ok let's go ahead. SQL Concat () function concatenates two separate character string into one character string. Let's see the syntax Concat (string_1 , String_2) Note here that SQL Concat function takes only two arguments at a time. This SQL Concat function will return string_1 concatenated with string_2. This also means that it will return a single string which is a combined string of parameter String_1 and String_2. Both the parameters of SQL Concat function String_1 and string_2 can be of any data-type. You can even specify the columns of the table here. SQL Concat function is equivalent to the concatenation operator (||). SQL concatenation operator is represented by double solid vertical bars or we can say double pipe signs. Question: How to concatenate more than two strings as SQL Concat that can have only 2 parameters and what is the difference between SQL Concat Function and SQL concatenation operator? The one answer for the second Question What is the Difference between SQL Concat Function and SQL concatenation operator? Is While SQL Concat function takes only two parameters, The Concat operator can be repeated as often as is necessary. Meaning, by the help of SQL Concat operator you can combine as many strings as you want. And Concatenation operator is also not supported by several databases such as SQL server so this might cause problem. To answer the first question How to concatenate more than two strings as SQL Concat that can have only 2 parameters? We will have to jump over SQL developer. Let's see some examples. Say we want to retrieve the full name of an employee from Employees table. Let's try it using SQL Concat function. SELECT Concat (first_name, last_name) AS "Full Name" FROM employees; Here in this query we use two column names - first_name and last_name as arguments of our Concat function Execute. As you can see here, we get full name of our employee but there is no space in between first name and last name. We will see how to format this string using SQL Concat function in a few seconds But before that, let's see how to do the same task using SQL concatenation operator. SELECT first_name ||last_name AS "Full name" FROM employees; As you can see this query also produces the same result. Now we will see how to format full name of employees First we will do this using SQL concatenation Operator. SELECT first_name||' '||last_name AS "Full name" FROM employees; Now you can see we get space between first name and last name of the employee. Again, let's do it using SQL Concat function. Here we will see the nested function concept where we will be using nested Concat function to achieve this formatted string. SELECT Concat (Concat (first_name, ' '), last_name) FROM employees; Inner Concat function has two parameters. These are our first column name first_name and an empty string which will be a space between first name and second name. This Concat will now return a string which is the first name with space. This returning string will be the first input of our Outer Concat and column last_name will be the second input. All together this will give us the desired output. As you can see this method is complex than the first one where we use SQL concatenation operator.
Views: 76997 Manish Sharma
IS NULL Operator in SQL Query with Example
 
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SQL IS NULL Operator: A column value is NULL if it does not exist. The IS NULL operator is used to display all the rows for columns that do not have a value. For Example: If you want to find the emp names who do not get any commision, the query would be as given below: select * from emp where COMM IS NULL; In the opposite way, NOT NULL also works here: select * from emp where COMM IS NOT NULL; Thanks for watching..:)
Views: 3500 WingsOfTechnology

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