how to put two field in one column..

[Dumb Fish]

hey...i need to ask ..how to put two field in one column?
let say,
i have one field call Quantity for weight. Now i need to put the quantity unit which is store in other field call unit. how i concat two field in one column....?

[rch1231]

concat(table1.field1, table2.field2) as newname

[Dumb Fish]

concat(table1.field1, table2.field2) as newname

thank I already finish.