The WHERE Clause

Restricts the records affected by an SQL statement. The syntax is:

WHERE condition-list

where "condition-list" is a comma-separated list of conditions for fields.

Another use of the WHERE clause is for joining tables together in order to combine fields from several tables. The syntax is:

WHERE tableName1.fieldName = tableName2.fieldName

This is a simple example of joining tables using an older SQL language specification. If you are using this method to join tables, then the FROM clause should list all tables as a comma-separated list.