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T-SQL WHERE Clause

Where clause is used to generate the conditions while obtaining data from a table or including it in other tables. If the condition is satisfied, then it returns a particular value from the table. We use WHERE clause to filter the records in database and to fetch the main records.

In a SELECT statement, we use the WHERE clause, but it also used in UPDATE, DELETE account, etc.

Syntax:

We are generating a condition using the logical operators, which are: >, <, =, LIKE, NOT etc.

Lets understand it using below example:

Example:

See the EMPLOYEES table which has the following records –

ID	Name	AGE	ADDRESS	Salary
001	Rahul	23	Kota	20000.00
002	Clinton	22	Mumbai	15000.00
003	Kamal	31	Delhi	25000.00
004	Chitra	28	Kanyakumari	65000.00
005	Santanu	26	Madhya Pradesh	38500.00
006	Savitri	24	Bhopal	4500.00
007	Manii	30	Indonesia	15000.00

The following command is an example that would fetch the ID, Name, and Salary fields from the EMPLOYEES table where salary is more significant than 2000.

Output of above query:

ID	NAME	SALARY
001	Rahul	22000.00
003	Kamal	25000.00
004	Chitra	65000.00
005	Santanu	38500.00

EXAMPLE: 1

The command fetches NAME, AGE, and Salary fields from the EMPLOYEES table. Where the name of employee is ‘Chitra.’

All strings must be generated inside the single quotes (”) where the numeric values used without any quote:

The command generates the given output.

NAME	AGE	SALARY
Chitra	28	65000.00

EXAMPLE: 2

The command fetches ID, and AGE fields from the EMPLOYEES table. Where the name of employee is ‘Chitra.’

The command generates the given output.

ID	AGE
007	30

EXAMPLE 3:

The below command is an example, which fetch the ID, Name, and Salary fields from the EMPLOYEES table where AGE is greater than 28.

Output:

ID	NAME	SALARY
003	Kamal	25000.00
007	Manii	15000.00

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