mysql - How to get data from two tables from database? -

can explain me, why code not working?

select sum(`cash`) `cash`,count(*) `rows` `table_1` `login` = 'test' union select count(*) `rows2` `table_2` `login` = 'test'; 

in phpmyadmin see message:

1222 - used select statements have different number of columns

and not solve problem.

a union takes results of multiple select statements , presents them single result set. in order this, number of columns in individual select statements has same.

to understand this, may format query bit:

    select         sum(`cash`) `cash`,         count(*) `rows`     `table_1`     `login` = 'test' union     select         count(*) `rows2`     `table_2`     `login` = 'test' 

your first query selecting 2 columns, cash , rows. second query selects 1 column, rows2. note since union concatenating results, may call corresponding columns in each query same name.

if don't have values want select second table, can substitute default value missing columns:

    select         sum(`cash`) `cash`,         count(*) `rows`     `table_1`     `login` = 'test' union     select         null `cash`         count(*) `rows`     `table_2`     `login` = 'test'