make part of PG ARRAY part of base types, look into ANY / ALL

[Mike Bayer]

ARRAY, array constructors, ANY, ALL, CONTAINS are all in DB2 as well not to mention the SQL standard. Oracle has VARRAY also which maybe we could support someday. this is needed for functions like #3132.

At the moment, PG still has its own operators like contains, contained_by, etc., so I still think people will want to use postgresql.ARRAY. However, for #3132, we need to do a check on the input type to see if it is already Array. So I think putting the basic expression stuff into sqltypes.Array would be helpful here, as would an implementation of ANY / ALL. Ideally ANY/ALL would be able to accept subqueries as well, also SQL standard. They are close to IN in that they accept a subquery in this way but not quite the same.

[Mike Bayer]

• build out a new base type for Array, as well as new any/all operators
• any/all work for Array as well as subqueries, accepted by MySQL
• Postgresql ARRAY now subclasses Array
• fixes #3516

→ <<cset 8594e9943111>>

[Mike Bayer]

not merged yet

[Mike Bayer]

• build out a new base type for Array, as well as new any/all operators
• any/all work for Array as well as subqueries, accepted by MySQL
• Postgresql ARRAY now subclasses Array
• fixes #3516

→ <<cset 7024745a142e>>