select mr==mr from mr not work

[j.yu@…]

select mr==mr from mr not work
also select 1==1 from mr not work

[Peter Baumann]

• "1==1" is not supported by rasql
• "mr==mr" needs to be written as "mr = mr" - maybe a documentation bug? → check

[Dimitar Misev]

Yes indeed, the ql guide says:

==, <, >, <=; >=, !=
For two MDD values (or evaluated MDD expressions), compare for each
coordinate the corresponding cells to obtain the Boolean result indicated
by the operation.
Note that comparison works on all atomic cell types. On composite types,
only == and != make sense with the meaning that, for two cells with
identical structure, all components undergo a pairwise comparison.

Should be fixed in the documentation.

[Dimitar Misev]

Additionally, select mr = mr from mr doesn't print t/f, this should also be fixed.

[Marcus Sen]

This documentation error caught me out as well (March 2012). I'm not sure what the comment about only == and != making sense for composite types means. Do we have to use a different equality comparison operator depending on the type we are comparing?

[Dimitar Misev]

It means the <, >, … on composite types are not supported, but only = and !=

[Peter Baumann]

adjusted documentation: no "==", but "=" to be used.