Hibernate - Like predicate

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Like predicate

Performs a like comparison on string values. The syntax is:

like_expression ::=
    string_expression
    [NOT] LIKE pattern_value
    [ESCAPE escape_character]

The semantics follow that of the SQL like expression. The pattern_value is the pattern to attempt to match in the string_expression. Just like SQL, pattern_value can use _ and % as wildcards. The meanings are the same. The _ symbol matches any single character and % matches any number of characters.

Like predicate examples

List<Person> persons = entityManager.createQuery(
"select p " +
"from Person p " +
"where p.name like 'Jo%'", Person.class )
.getResultList();

 List<Person> persons = entityManager.createQuery(
"select p " +
"from Person p " +
"where p.name not like 'Jo%'", Person.class )
.getResultList();
The optional escape 'escape character' is used to specify an escape character used to escape the special meaning of _ and % in the pattern_value. This is useful when needing to search on patterns including either _ or %.

The syntax is formed as follows: 'like_predicate' escape 'escape_symbol' So, if | is the escape symbol and we want to match all stored procedures prefixed with Dr_, the like criteria becomes: 'Dr|_%' escape '|':

Like with escape symbol

// find any person with a name starting with "Dr_"
List<Person> persons = entityManager.createQuery(
"select p " +
"from Person p " +
"where p.name like 'Dr|_%' escape '|'", Person.class )
.getResultList();

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