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SQL Basic Concepts
With IN clause, we can specify multiple values in a WHERE clause. For example, in case of “IN”, one can use the subquery to get the multiple values in the IN clause or we can have predefined values. In this article, we are going to use the following table for some examples:-CREATE TABLE [dbo]. [Employee]([Empid] […]
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And & Or:- These Operators are used to further filter the recordset return by SQL queries when more than one conditions are specified. In case of “AND” all the conditions must be true and in case of “OR” any of the condition must be true. In this article, we are going to use the table […]
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Except command in SQL Server returns the distinct values from the left query that are not also found on the right query. For Except command, below basic rules must be followed. The number and the order of the columns must be the same in all queries. The data types must be compatible. Syntax { query_specification […]
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This function is used to returns distinct values that are returned by both the query on the left and right sides of the INTERSECT operand. For intersection command, below basic rules must be followed. The number and the order of the columns must be the same in all queries. The data types must be compatible. […]
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While loop in SQL server Introduction In While loop, we set a condition for the repeated execution of a Code block. So we use while loop in SQL Server to repeat execution of a SQL Code block or a SQL Statement till the condition in the while loop is satisfied. Once the condition is failed, the […]
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Stuff VS Replace function Stuff Function This function is used to replace string from the given start position, passed as 2nd argument with string passed as last argument. In Stuff function, 3rd argument defines the number of characters which are going to be replaced. Syntax:- STUFF ( character_expression , start , length , replaceWith_expression ) […]
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Case Statement/ Expression in SQL server Sometimes we need to get one result output from multiple possible outcomes based on the evaluation of some expression. This expression can be a simple case expression which compares an expression with a set of Expression/Values to determine the result or it can be a search case expression where […]
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Many times we need to alter the table definition by adding , deleting or updating a column in the table. In this article, I am trying to explain the following :- 1. How to add a column 2. How to update a column 3. How to drop a column Suppose we have a table say […]
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Table variable:- SQL Server provides an variable known as table variable which is used to store data in a similar way as we store data in physical tables but with some limitations. Like other SQL variable, it is also declare with the help of the Declare keyword with @ prefix. The Syntax of declaring a table variable is […]
Continue ReadingTo change the collation of an database following commands can be used: ALTER DATABASE [database name] SET SINGLE_USER WITH ROLLBACK IMMEDIATE ALTER DATABASE [database name] COLLATE Newcollation ALTER DATABASE [database name] SET MULTI_USER For example , suppose if the name of your database is learningdb and you want to change the collation to the collation SQL_Latin1_General_CP1257_CI_AS, then following commands can be used:- ALTER DATABASE learningdb SET SINGLE_USER WITH ROLLBACKIMMEDIATE ALTER DATABASE learningdb COLLATE SQL_Latin1_General_CP1257_CI_AS ALTER DATABASE learningdb SET MULTI_USER
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