Calling fbsql_fetch_assoc() is equivalent to calling fbsql_fetch_array() with FBSQL_ASSOC as second parameter. It only returns an associative array.
An important thing to note is that using fbsql_fetch_assoc() is NOT significantly slower than using fbsql_fetch_row(), while it provides a significant added value.
Returns an associative array that corresponds to the fetched row, or FALSE if there are no more rows.
If two or more columns of the result have the same field names, the last column will take precedence. To access the other column(s) of the same name, you must use fbsql_fetch_array() and have it return the numeric indices as well.