Merge Data Tables in PHP with UNION

In PHP, merging multiple tables can be achieved by using the UNION operator in SQL statements. This operator is used to combine the result sets of two or more SELECT statements, returning a result set containing all rows.

For example, assuming there are two data tables, table1 and table2, you can merge them using the following SQL statement:

$sql = "SELECT * FROM table1
        UNION
        SELECT * FROM table2";

The statement combines all rows from table1 and table2 into one result set. The merged result set can be sorted, filtered, and manipulated as needed.