like
like/LIKE is a logical operator that is used to retrieve the data in a column of a table, based on a specified pattern. It is equivalent to function like.
Syntax
match_expression [NOT] LIKE pattern
match_expression is a column name or an expression containing column name.
pattern is a string (case sensitive) to be searched in match_expression. The following wildcards can be used:
- % represents zero, one or multiple characters.
- ? represents one character.
If match_expression matches pattern, it returns true, otherwise returns false. If "not" is specified, an opposite result is returned. The like keyword is usually used in a where clause to filter data based on a specific pattern. For example, to select data that starts with "A", ends with "B", or contains "Ca".
Examples
t= table(`a1`a2`a3`b1`b2`b3`c1`c2 as id, 7 4 NULL 1 8 NULL 12 NULL as val) select * from t where id like "a%" //equivalent to select * from t where like(id, "a%")
id | val |
---|---|
a1 | 7 |
a2 | 4 |
a3 |
select * from t where id not like "a%"
id | val |
---|---|
b1 | 1 |
b2 | 8 |
b3 | |
c1 | 12 |
c2 |