Question

I need to run the following update script

update table1 set col1 = 'xxxx', 
col2 = (select cc.client_type
        from table2 t2, table3 t3, table1 t1
        where t2.col3='YYY' 
        AND t3.col4 != 'aaa'
        AND t3.col5 = 'Y'
)

I am getting following error

Error report:
SQL Error: ORA-01427: single-row subquery returns more than one row
01427. 00000 -  "single-row subquery returns more than one row"

I am using Oracle 10g. Any help on this??

Answer 1

update table1 t set col1='xxx',
col2= (select cc.client_type from table2 t2, table3 t3
where t2.col3='YYY' 
    AND t3.col4 != 'aaa'
    AND t3.col5 = 'Y'
    AND t2.random_col=t3.random_col)

will update necessary record (provided inner query returns only one row). However, it will be a constant value (where random_col is some column which can be associated with both table2 and table3, random_col2 is some column which can be associated with both table3 and table1)

Another possibility can be :-

update table1 t set col1='xxx',
    col2= (select cc.client_type from table2 t2, table3 t3
    where t2.col3='YYY' 
        AND t3.col4 != 'aaa'
        AND t3.col5 = 'Y'
        AND t2.random_col=t3.random_col
        AND t3.randome_col2=t.random_col2)

The above will update table1 with different(or same) values depending on table2 and table3