Add InTuples expression for multi-column IN expression

[rbygrave]

Example

    var c = QContact.alias();

    InTuples inTuples = InTuples.of(c.firstName, c.lastName)
      .add("Rob", "B")
      .add("Bob", "C")
      .add("Mob", "D");

    var query = new QContact()
      .firstName.isNotNull()
      .email.isNotNull()
      .inTuples(inTuples)
      .query();

    query.findList();
    assertThat(query.getGeneratedSql()).contains("(t0.first_name,t0.last_name) in ((?,?),(?,?),(?,?))");

Note this is currently not supported by SQLServer or DB2.

[rPraml]

Hi @rbygrave

I like that feature, unfortunately it will not work on all databases.

On DB2 you have to use where (prop1, prop2) in ( VALUES (?,?),(?,?) ...) (Same syntax works on MariaDB)

On SqlServer, you have to do other tricks, like subqueries or just a simple conjunction of ANDs / ORs.
See: https://stackoverflow.com/questions/8006901/using-tuples-in-sql-in-clause

BTW: What do you think about this syntax?

 var query = new QContact()
      .firstName.isNotNull()
      .email.isNotNull()
      .inTuples(c.firstName, c.lastName)
         .add("Rob", "B")
         .add("Bob", "C")
         .add("Mob", "D")
      .endTuple()
      .query();

Roland.

[rbygrave]

DB2

Oh, I didn't know DB2 supported it via that syntax with VALUES - interesting and maybe we can support that. I was ok with putting this into the next version knowing it does not work with SQLServer and DB2.

SQLServer

Yes. It's almost easier to use concat functions and use a plain IN which is what we have with inPairs() (noting that only supports 2 columns).

BTW: What do you think about this syntax?

Well I expect the normal case is that we have a collection of things ... and iterate the collection calling add(...). That is, I don't think we will do this in-line in the query much at all.

Hmmm, let me think about it. endTuple() is consistent with endOr().

[rPraml]

SQLServer

Yes. It's almost easier to use concat functions and use a plain IN which is what we have with inPairs() (noting that only supports 2 columns).

Do you plan to make a fallback implementation for platforms that do not support tuples? I really like that, as we are often using this here (we use and/or queries), so it would be great, if we can get some benefits, if the platfrom supports it

Some thoughts:

• concat: easy to implement, will make problems on special data types where java.toString differs from server.toString (e.g. dates + times)
• combination of AND/OR: Should be also easy to implement, but makes complex queries
• some complex subquery: would make query less complex (=shorter) but difficult to implement

[rbygrave]

Do you plan to make a fallback implementation for platforms that do not support tuples?

Yes, that is the plan. I'll look to release as it is in 13.20.1 and add an implementation for DB2 & SQLServer later. [Rant, why is it that 2 of the largest tech companies on the planet can't implement this like everyone else ??? ]

combination of AND/OR:

This is what I thought InTuples will have to do for SQLServer. In theory people can do the concat + IN today but perhaps need guidance / example to show them.