SQL create temporary table

When querying data in the database , For example, query out type According to the unused value , Another alias , It's a little troublesome to cycle through the program , Now there is a way to connect the temporary table with the query table to query . So now you need to create a new temporary table , Then use the left join to join the query .

1、 Create a new temporary table

select '100' as val,'sc' as lx UNION select '200' as val,'zy' as lx UNION select '300' as val,'bg' as lx UNION select '600' as val,'yy' as lx 

2、 Link query

select ty.*,ta.* from table ta left join (select '100' as val,'sc' as lx UNION select '200' as val,'zy' as lx UNION select '300' as val,'bg' as lx UNION select '600' as val,'yy' as lx ) ty on ty.lx=ta.lx