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  • postgresql 分页查询

    postgresql 分页查询

    https://blog.csdn.net/qq_28289405/article/details/81484545

    PostgreSQL的LIMIT子句是用来限制由SELECT语句返回的数据量。

    通俗的讲解:

    官方的讲解:

    语法:

    LIMIT子句的SELECT语句的基本语法如下:

    SELECT column1, column2, columnN
    FROM table_name
    LIMIT [no of rows] 

    以下是LIMIT子句时使用OFFSET子句的语法:

    SELECT column1, column2, columnN
    FROM table_name
    LIMIT [no of rows] OFFSET [row num]  

    LIMIT,OFFSET允许只检索部分查询所产生的行。 www.yiibai.com

    实例:

    考虑表公司有如下记录:

     select * from COMPANY;
     id | name  | age | address   | salary
    ----+-------+-----+-----------+--------
      1 | Paul  |  32 | California|  20000
      2 | Allen |  25 | Texas     |  15000
      3 | Teddy |  23 | Norway    |  20000
      4 | Mark  |  25 | Rich-Mond |  65000
      5 | David |  27 | Texas     |  85000
      6 | Kim   |  22 | South-Hall|  45000
      7 | James |  24 | Houston   |  10000
    (7 rows)
    

    下面是一个例子,这限制了表中的一行,根据从表中读取想要的行: yiibai.com

    testdb=# SELECT * FROM COMPANY LIMIT 4;  
    

    这将产生以下结果:

     id | name  | age | address     | salary
    ----+-------+-----+-------------+--------
      1 | Paul  |  32 | California  |  20000
      2 | Allen |  25 | Texas       |  15000
      3 | Teddy |  23 | Norway      |  20000
      4 | Mark  |  25 | Rich-Mond   |  650
    (4 rows)
    

    但在某些情况下,可能要选出一组记录从一个特定的偏移。下面是一个例子,从第三位开始取出3条:

    testdb=# SELECT * FROM COMPANY LIMIT 3 OFFSET 2;  
    

    这将产生以下结果:

    id | name  | age | address   | salary
    ----+-------+-----+-----------+--------
      3 | Teddy |  23 | Norway    |  20000
      4 | Mark  |  25 | Rich-Mond |  65000
      5 | David |  27 | Texas     |  85000
    (3 rows) 

    参考: PostgreSQL LIMIT子句

               postgreSQL数据库limit分页、排序

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  • 原文地址:https://www.cnblogs.com/handsome1013/p/10396720.html
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