MySQL一个语句查出各种整形占用字节数及最大最小值的实例_Mysql

MySQL一个语句查出各种整形占用字节数及最大最小值的实例

2020-07-21 16:25MYSQL教程网 Mysql

下面小编就为大家带来一篇MySQL一个语句查出各种整形占用字节数及最大最小值的实例。

直接上码：

				?

									select 'bigint unsigned' as type ,'8' as bytes ,~0 as max_num,0 as min_num union

									select 'int unsigned','4',~0>>32,0 union

									select 'mediumint unsigned','3',~0>>40,0 union

									select 'smallint unsigned','2',~0>>48,0 union

									select 'tinyint unsigned','1',~0>>56,0 union

									select 'signed bigint','8',~0>>1,-(1<<63) union

									select 'signed int','4',~0>>33,-(1<<31) union

									select 'signed mediumint','3',~0>>41,-(1<<23) union

									select 'signed smallint','2',~0>>49,-(1<<15) union

									select 'signed tinyint','1',~0>>57,-(1<<7);

									+--------------------+-------+----------------------+----------------------+

									| type    | bytes | max_num    | min_num    |

									+--------------------+-------+----------------------+----------------------+

									| bigint unsigned | 8  | 18446744073709551615 |     0 |

									| int unsigned  | 4  |   4294967295 |     0 |

									| mediumint unsigned | 3  |    16777215 |     0 |

									| smallint unsigned | 2  |    65535 |     0 |

									| tinyint unsigned | 1  |     255 |     0 |

									| signed bigint  | 8  | 9223372036854775807 | -9223372036854775808 |

									| signed int   | 4  |   2147483647 |   -2147483648 |

									| signed mediumint | 3  |    8388607 |    -8388608 |

									| signed smallint | 2  |    32767 |    -32768 |

									| signed tinyint  | 1  |     127 |     -128 |

									+--------------------+-------+----------------------+----------------------+

									rows in set (0.00 sec)