SQL WHERE |
SQL Sample Code - SQL WHERE clause |
| SELECT column_name(s) FROM table_name WHERE column_name operator value; |
See the SQL samples section below for an explanation of the WHERE clause.
Notes:- Use single quotes around text. Most database vendors will also allow double quotes too.
Numeric values should not use quotations.
What does the SQL WHERE clause do? |
The SQL WHERE clause searches for a condition specified in the WHERE part of the statement, and retrieves only those records which satisfy that condition.
A variety of criteria and operators can be used in the WHERE clause.
Sample 1 – SQL WHERE |
In this SQL sample we will use the database table ‘tblCompany’.
| Company_ID | CompanyName | Address | Town |
| 1 | SQL Sample | 1 Sample St | Hamburg |
| 2 | SQL Code Land | 2 Code Rd | Hamburg |
| 3 | Sample Code World | 66 SQL St | Curry |
| 4 | SQL Reference Ltd | 34 Reference St | Pisa |
In this SQL sample we only want to retrieve all the Columns from the tblCompany table whose company is based in the town of Hamburg.
Use the SELECT statement below:
| SELECT * FROM tblCompany WHERE Town = ‘Hamburg’; |
Use the SELECT statement below:
The table of results will look like this:
| Company_ID | CompanyName | Address | Town |
| 1 | SQL Sample | 1 Sample St | Hamburg |
| 2 | SQL Code Land | 2 Code Rd | Hamburg |
Quotations and Numeric Values.
Use single quotes around text. Most database vendors will also allow double quotes too.
Numeric values should not use quotations.
Sample 2 – SQL WHERE |
In this SQL sample we will use the database table ‘tblCompany’.
| Company_ID | CompanyName | Address | Town | Sales |
| 1 | SQL Sample | 1 Sample St | Hamburg | 10000 |
| 2 | SQL Code Land | 2 Code Rd | Hamburg | 20000 |
| 3 | Sample Code World | 66 SQL St | Curry | 18000 |
| 4 | SQL Reference Ltd | 34 Reference St | Pisa | 17000 |
In this SQL sample we only want to retrieve all the Columns from the tblCompany table whose Sales are over £10000.
Use the SELECT statement below:
| SELECT * FROM tblCompany WHERE Sales >10000; |
The table of results will look like this:
| Company_ID | CompanyName | Address | Town | Sales |
| 2 | SQL Code Land | 2 Code Rd | Hamburg | 20000 |
| 3 | Sample Code World | 66 SQL St | Curry | 18000 |
| 4 | SQL Reference Ltd | 34 Reference St | Pisa | 17000 |
WHERE Operators that can be used.
| Operator | Description |
| = | Equal to |
| <> | Not Equal To |
| > | Greater Than |
| < | Less Than |
| >= | Greater than or equal To |
| <= | Less than or equal to |
| LIKE | SQL LIKE allows you to perform pattern matching in the criteria rather an exact match. Like can be used in conjunction with % |
| BETWEEN | Between an inclusive range |
| IN | Can retrieve results based upon multiple known criteria. |
Related SQL Sample Code:
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