PostgreSQL 数据类型

谁借莪１个温暖的怀抱￠ 2022-11-27 06:29 125阅读 0赞

参考文章： [PostgreSQL 数据类型][PostgreSQL]

<table> 
 <thead> 
  <tr> 
   <th style="width:85px;">分类</th> 
   <th style="width:205px;">名称</th> 
   <th style="width:84px;">存储空间</th> 
   <th style="width:230px;">范围</th> 
   <th>描述</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td style="width:85px;">数值类型</td> 
   <td style="width:205px;">int2/smallint</td> 
   <td style="width:84px;">2 bytes</td> 
   <td style="width:230px;">-32768 到 +32767</td> 
   <td>small-range integer</td> 
  </tr> 
  <tr> 
   <td style="width:85px;">数值类型</td> 
   <td style="width:205px;">int4/integer</td> 
   <td style="width:84px;">4 bytes</td> 
   <td style="width:230px;">-2147483648 到 +2147483647</td> 
   <td>typical choice for integer</td> 
  </tr> 
  <tr> 
   <td style="width:85px;">数值类型</td> 
   <td style="width:205px;">int8/bigint</td> 
   <td style="width:84px;">8 bytes</td> 
   <td style="width:230px;">-9223372036854775808 到 +9223372036854775807</td> 
   <td>large-range integer</td> 
  </tr> 
  <tr> 
   <td style="width:85px;">数值类型</td> 
   <td style="width:205px;">decimal/NUMERIC</td> 
   <td style="width:84px;">变长</td> 
   <td style="width:230px;">无限制</td> 
   <td>decimal(6,5) 数字长度为6，一位整数，5位小数，最后四舍五入</td> 
  </tr> 
  <tr> 
   <td style="width:85px;">数值类型</td> 
   <td style="width:205px;">float4/REAL</td> 
   <td style="width:84px;">4 bytes</td> 
   <td style="width:230px;">&nbsp;</td> 
   <td>7位小数，第七位是四舍五入上来的</td> 
  </tr> 
  <tr> 
   <td style="width:85px;">数值类型</td> 
   <td style="width:205px;">float8/DOUBLE PRECISION</td> 
   <td style="width:84px;">8 bytes</td> 
   <td style="width:230px;">&nbsp;</td> 
   <td>16位小数，第16位以后舍去？</td> 
  </tr> 
  <tr> 
   <td style="width:85px;">数值类型</td> 
   <td style="width:205px;">serial2/SMALLSERIAL NOT NULL</td> 
   <td style="width:84px;">2 bytes</td> 
   <td style="width:230px;">1 到 32767</td> 
   <td>小自增整数</td> 
  </tr> 
  <tr> 
   <td style="width:85px;">数值类型</td> 
   <td style="width:205px;">serial4/SERIAL NOT NULL</td> 
   <td style="width:84px;">4 bytes</td> 
   <td style="width:230px;">1 到 2147483647</td> 
   <td>&nbsp;</td> 
  </tr> 
  <tr> 
   <td style="width:85px;">数值类型</td> 
   <td style="width:205px;">serial8/BIGSERIAL NOT NULL</td> 
   <td style="width:84px;">8 bytes</td> 
   <td style="width:230px;">1 到 9223372036854775807</td> 
   <td>&nbsp;</td> 
  </tr> 
  <tr> 
   <td style="width:85px;">货币类型</td> 
   <td style="width:205px;">money</td> 
   <td style="width:84px;">8 bytes</td> 
   <td style="width:230px;">&nbsp;</td> 
   <td>不会进行四舍五入</td> 
  </tr> 
  <tr> 
   <td style="width:85px;">字符类型</td> 
   <td style="width:205px;">varchar(n)</td> 
   <td style="width:84px;">&nbsp;</td> 
   <td style="width:230px;">&nbsp;</td> 
   <td>CHARACTER VARYING(64) 限制长度<br> CHARACTER VARYING 不限量</td> 
  </tr> 
  <tr> 
   <td style="width:85px;">字符类型</td> 
   <td style="width:205px;">char(n)</td> 
   <td style="width:84px;">&nbsp;</td> 
   <td style="width:230px;">&nbsp;</td> 
   <td>一般不用，与varchar有区别</td> 
  </tr> 
  <tr> 
   <td style="width:85px;">字符类型</td> 
   <td style="width:205px;">text</td> 
   <td style="width:84px;">&nbsp;</td> 
   <td style="width:230px;">&nbsp;</td> 
   <td> <p>&nbsp;</p> <p>&nbsp;</p> </td> 
  </tr> 
  <tr> 
   <td style="width:85px;">时间类型</td> 
   <td style="width:205px;">timestamp/TIMESTAMP(6) WITHOUT TIME ZONE</td> 
   <td style="width:84px;">8 bytes</td> 
   <td style="width:230px;">&nbsp;</td> 
   <td>&nbsp;</td> 
  </tr> 
 </tbody> 
</table>

[PostgreSQL]: https://www.cnblogs.com/duchaoqun/p/13024107.html