What are various Wildcards and How to use them in SQL Server

SQL Server Wildcards 
SQL wildcards can substitute for one or more characters when searching for data in a database.
SQL wildcards must be used with the SQL LIKE operator.
The wild cards can be "%" , "_", "[abc]"... as explained below

Example :
Suppose we have an Employee Table as follows :

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The Wild Card '%' Usage :
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Criteria-I:
To select Employees whose name Starts with Ravi

Select *from EMPLOYEE E WHERE E.E_Name LIKE 'ravi%'

The "%" sign can be used to define wildcards (missing letters in the pattern) both before and after the pattern.

Result:

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Criteria-II:
To select Employees whose name Ends with Reddy

Select *from EMPLOYEE E WHERE E.E_Name LIKE '%reddy'

Result:

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Criteria-III:
To select Employees whose name contains 'Kumar'

Select *from EMPLOYEE E WHERE E.E_Name LIKE '%kumar%'

Result:

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Criteria-IV:
To select Employees whose name NOT contains 'Reddy'

Select *from EMPLOYEE E WHERE E.E_Name NOT LIKE '%reddy%'

Result:

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The Wildcard '_' Usage :
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Criteria-I:
Now we use the Wildcard '_' to select Employees whose name starts with any character followed by 'arun'

Select *from EMPLOYEE E WHERE E.E_Name LIKE '_arun'

Result:

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The Wildcards '[abc]' and '[a-c]' Usage :
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Criteria-I:
Now we use the Wildcard '[rst]' to select Employees whose name starts with any of the characters 'R' or 'S' or 'T'.'

Select *from EMPLOYEE E WHERE E.E_Name LIKE '[RST]%'
OR
Select *from EMPLOYEE E WHERE E.E_Name LIKE '[R-T]%'

Result:

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Criteria-II:
Now we use the Wildcard '[rst]' to select Employees whose name NOT starts with any of the characters 'R' or 'S' or 'T'.'

Select *from EMPLOYEE E WHERE E.E_Name NOT LIKE '[RST]%'

Result:

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Thanks, TAMATAM ; Business Intelligence & Analytics Professional

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