SQL 之 多表联合更新

Posted 2020-07-08 Now,DayBreak

1、 sqlite 多表更新方法

UPDATE tA SET col1=tB.col1
FROM tableA tA INNER JOIN tableB tB ON tA.col2=tB.col2

　　这是一个非常简单的批量更新语句 在SqlServer中支持此语法 sqlite中却不支持，sqlite中可转换为如下语法：

UPDATE tableA SET col1=(SELECT col1 FROM tableB WHERE col2=tableA.col2)

2、SQL Server 多表更新方法

UPDATE { table_name WITH ( < table_hint_limited > [ ...n ] ) | view_name | rowset_function_limited } 
SET { column_name = { expression | DEFAULT| NULL } | @variable = expression | @variable = column = expression } [ ,...n ]
{ { [ FROM { < table_source > } [ ,...n ] ] 
[ WHERE < search_condition > ] } | [WHERE CURRENT OF { { [ GLOBAL ] cursor_name } | cursor_variable_name } ] } 
[ OPTION ( < query_hint > [ ,...n ] ) ]

　　SQL Server示例:

UPDATE tA SET tA.col1=tB.col1,tA.col2=tB.col2 
FROM tableA tA,tableB tB 
WHERE tA.col3=tB.col3

3、access数据库多表更新方法
x = "update " + DLTB + " a inner join tbarea2 b  on a.objectid=b.FID  set a." + fd_dltb_xzdwmj + "=b.area_xzdw, a." + fd_dltb_lxdwmj + "=b.area_lxdw";
SQLList.Add(x);

4、Oracle 多表更新方法
Oracle语法:
UPDATE updatedtable
SET (col_name1[,col_name2...])=(SELECT col_name1,[,col_name2...] FROM srctable
        [WHERE where_definition])

Oracel 示例:
UPDATE landleveldata a set (a.gqdltks, a.bztks)= (select b.gqdltks,
b.bztks from gdqlpj b where a.GEO_Code=b.lxqdm)

5、mysql 多表更新方法
MySQL语法:
UPDATE table_references SET col_name1=expr1 [, col_name2=expr2 ...]
[WHERE where_definition]

MySQL 示例:
UPDATE landleveldata a, gdqlpj b
SET a.gqdltks= b.gqdltks, a.bztks=b.bztks
WHERE a.GEO_Code=b.lxqdm