AND OR

we have seen that the WHERE keyword can be used to conditionally select data from a table. This condition can be a simple condition (like the one presented in the previous section), or it can be a compound condition. Compound conditions are made up of multiple simple conditions connected by AND or OR. There is no limit to the number of simple conditions that can be present in a single SQL statement.

The syntax for a compound condition is as follows:

SELECT "column_name"
FROM "table_name"
WHERE "simple condition"
{[AND|OR] "simple condition"}+

The {}+ means that the expression inside the bracket will occur one or more times. Note that AND and OR can be used interchangeably. In addition, we may use the parenthesis sign () to indicate the order of the condition.