問題文
A variable is declared with the %TYPE attribute against a column of a table, and the column carries a not null constraint and a default value. Which description of what the variable takes from that column is correct?
選択肢
- It takes nothing from the column while the block runs, it fixes the data type at the moment of compilation, and it keeps that type even after the column of the table is altered.
- It takes the data type and the size of the column, it also takes the default value that the column declares, and it starts out holding that default value when the block begins.
- It takes the data type and the size of the column, it leaves the not null constraint of the column behind, and it starts out as null unless the declaration assigns a value.
- It takes the size of the column but not the data type, it takes the check condition written on the column, and it starts at the value held in the first row of the table.