How can I split the column data into rows with basic SQL.
COL1 COL2
1 A-B
2 C-D
3 AAA-BB
Result
COL1 Col2
1 A
1 B
2 C
2 D
3 AAA
3 BB
4 Answers
From Oracle 12, if it is always two delimited values then you can use:
SELECT t.col1,
l.col2
FROM table_name t
CROSS JOIN LATERAL (
SELECT SUBSTR(col2, 1, INSTR(col2, '-') - 1) AS col2 FROM DUAL
UNION ALL
SELECT SUBSTR(col2, INSTR(col2, '-') + 1) FROM DUAL
) l
Which, for the sample data:
CREATE TABLE table_name (COL1, COL2) AS
SELECT 1, 'A-B' FROM DUAL UNION ALL
SELECT 2, 'C-D' FROM DUAL UNION ALL
SELECT 3, 'AAA-BB' FROM DUAL;
Outputs:
COL1 COL2 1 A 1 B 2 C 2 D 3 AAA 3 BB
db<>fiddle here
Comments
Snowflake is tagged, so here's the snowflake way of doing this:
WITH TEST (col1, col2) as
(select 1, 'A-B' from dual union all
select 2, 'C-D' from dual union all
select 3, 'AAA-BB' from dual
)
SELECT test.col1, table1.value
FROM test, LATERAL strtok_split_to_table(test.col2, '-') as table1
ORDER BY test.col1, table1.value;
Comments
As of Oracle:
SQL> with test (col1, col2) as
2 (select 1, 'A-B' from dual union all
3 select 2, 'C-D' from dual union all
4 select 3, 'AAA-BB' from dual
5 )
6 select col1,
7 regexp_substr(col2, '[^-]+', 1, column_value) col2
8 from test cross join
9 table(cast(multiset(select level from dual
10 connect by level <= regexp_count(col2, '-') + 1
11 ) as sys.odcinumberlist))
12 order by col1, col2;
COL1 COL2
---------- ------------------------
1 A
1 B
2 C
2 D
3 AAA
3 BB
6 rows selected.
SQL>
Comments
For MS-SQL 2016 and higher you can use:
SELECT Col1, x.value
FROM t CROSS APPLY STRING_SPLIT(t.Col2, '-') as x;
BTW: If Col2 contains null, it does not appear in the result.
-to denote splits and you could have A-B-C-D and need 4 rows?