合并两个表并填写mysql中缺少的值

合并两个表并填写mysql中缺少的值,mysql,Mysql,我在MySQL中有以下两个表: 表1: ID Val1 1 100 2 200 3 300 表2: ID Val2 2 50 我怎样才能把它们组合成这样一张桌子呢 ID Val1 Val2 1 100 0 2 200 50 3 300 0 使用LEFT JOIN与IFNULL()一起为Val2填充零 SELECT Table1.ID, Table1.Val1, IFNULL(Table2.Val2, 0) AS Val2 FROM Table1 LEFT

我在MySQL中有以下两个表:

表1:

ID Val1
1  100
2  200
3  300
表2:

ID Val2
2  50
我怎样才能把它们组合成这样一张桌子呢

ID Val1 Val2
1  100  0
2  200  50
3  300  0

使用
LEFT JOIN
IFNULL()
一起为Val2填充零

SELECT 
  Table1.ID,
  Table1.Val1,
  IFNULL(Table2.Val2, 0) AS Val2
FROM Table1 LEFT JOIN Table2 ON Table1.ID = Table2.ID
SELECT 
  Table1.ID,
  Table1.Val1,
  IFNULL(Table2.Val2, 0) AS Val2
FROM Table1 LEFT JOIN Table2 ON Table1.ID = Table2.ID
SELECT Table1.ID, Table1.Val1, COALESCE(Table2.Val2, 0) AS Val2
FROM Table1 LEFT OUTER JOIN Table2 USING (ID)
INTO NewTable