Usted buscó: arithmetic (Chino (Simplificado) - Inglés)

后退( b) arithmetic exercise
& back

和( and) @ label: textbox operand to the arithmetic filter function
operand and data

columns without a field name (e.g., results of arithmetic operations) and empty fields are not stored in the array. also, if two or more columns of the result have the same column names, the later column will take precedence. in this situation, either call sesam_fetch_row() or make an alias for the column.
select tbl1.col as foo, tbl2.col as bar from tbl1, tbl2