MySQL: Add to table3 if record from table1 has a count of 0 or 1 in table 2 -

MySQL: Add to table3 if record from table1 has a count of 0 or 1 in table 2 -

basically i'm trying build table (we'll phone call table3) has records table1 have counts of 0, 1, or not appear @ in table2. table1 , table3 in database1 , table2 in database2.

here closest can getting working.

insert database1.table3 (col1, col2, ...) select t1.col1, t1.col2, ... database1.table1 t1 left bring together database2.table2 t2 on t1.columntomatch = t2.columntomatch (t2.count < 2);

tldr: want table1 doesn't appear in table2 added table3. if record in table1 appears in table2 want include in table3 if table2.count 0 or 1.

thank you

welcome so.

you looking left excluding join - see here

to records table1 doesn't appear in table2 a

select table1.* table1 left bring together table2 on table1.columntomatch = table2.columntomatch table2.columntomatch null

after matchting records count 0 or 1:

select table1.* database1.table1 t1 inner bring together database2.table2 on table1.columntomatch = table2.columntomatch table2.count in (0, 1)

then can append both results union all , store whole bunch in new table:

create table table3 select ... ... union select ... ...

mysql