1z0-883 第4题

jikcheng

When designing an InnoDB table, identify an advantage of using the BIT datatype Instead of one of the integer datatypes.
A.  BIT columns are written by InnoDB at the head of the row, meaning they are always the first to be retrieved.
B.  Multiple BIT columns pack tightly into a row, using less space.
C.  BIT (8) takes less space than eight TINYINT fields.
D.  The BIT columns can be manipulated with the bitwise operators &, |, ~, ^, <<, and >>. The other integer types cannot.

jikcheng

原文翻译：

你定义了一个innodb 存储引擎的表，用BIT 类型 而不是用一个int 类型的优势是什么。

jikcheng

Answer: B Explanation:

BIT(8)  要比TINYINT（8） 使用的空间要少的多。因为一个TIINYINT （1） 就是一个BIT(8).