问题
I have two tables, table03 have 10 rows and table01 have 21 rows, now I want to get rows from table03 where they don't exist in table01, so far I wrote this query but it shows all rows of table03 even some rows doesn't exist on table01.
SELECT T3.`DateAdded`, T3.`Query_name`, T3.`Fund`, T3.`Ticker`
FROM `table_name03` T3 LEFT JOIN `table_name01` T1
ON T3.`DateAdded` = T1.`DateAdded`
AND `T3`.`Query_name` = `T1`.`Query_name`
AND `T3`.`Fund` = `T1`.`Fund`
AND `T3`.`Ticker` = `T1`.`Ticker`
Table03:
Table01:
回答1:
You are on the right track. You can just add a where
condition to filter on unmatched rows:
SELECT T3.DateAdded, T3.Query_name, T3.Fund, T3.Ticker
FROM table_name03 T3
LEFT JOIN table_name01 T1
ON T3.DateAdded = T1.DateAdded
AND T3.Query_name = T1.Query_name
AND T3.Fund = T1.Fund
AND T3.Ticker = T1.Ticker
WHERE T1.DateAdded IS NULL
You can also use not exists
:
SELECT T3.DateAdded, T3.Query_name, T3.Fund, T3.Ticker
FROM table_name03 T3
WHERE NOT EXISTS (
SELECT 1
FROM table_name01 T1
WHERE
T3.DateAdded = T1.DateAdded
AND T3.Query_name = T1.Query_name
AND T3.Fund = T1.Fund
AND T3.Ticker = T1.Ticker
)
来源:https://stackoverflow.com/questions/61110587/mysql-select-rows-that-from-table01-that-doesnt-exist-on-table02