Merging sql tables with multiple similar rows MYSQL -


i have following mysql table:

col1      col2        col3       col4       col5         abc         val2       null       null         abc         null       val3       val4 b         def         value2     null       value3 b         def         null       value4     null

i want output as

col1      col2        col3       col4       col5         abc         val2       val3       val4 b         def         value2     value4     value3

what should query?

you should use group by:

mysql> create table t3 (col1 varchar(16), col2 varchar(16), col3 varchar(16), col4 varchar(16), col5 varchar(16)); query ok, 0 rows affected (0.08 sec)  mysql> insert t3 (col1, col2, col3, col4, col5) values ('a', 'abc', 'val2', null, null), ('a', 'abc', null, 'val3', 'val4'), ('b', 'def', 'value2', null, 'value3'), ('b', 'def', null, 'value4', null); query ok, 4 rows affected (0.00 sec) records: 4  duplicates: 0  warnings: 0  mysql> select col1, max(col2), max(col3), max(col4), max(col5) t3 group col1; +------+-----------+-----------+-----------+-----------+ | col1 | max(col2) | max(col3) | max(col4) | max(col5) | +------+-----------+-----------+-----------+-----------+ |    | abc       | val2      | val3      | val4      | | b    | def       | value2    | value4    | value3    | +------+-----------+-----------+-----------+-----------+ 2 rows in set (0.01 sec)

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