Hi,

 

I'm attempting to declare a query string to execute in MonetDB. The documentation is not clear if this is possible, but other engines allow this functionality (such as MySQL and MS SQL Sever). Trying the following

 

    execute 'select * from tables';

 

fails with the message

 

    Error: syntax error, unexpected STRING, expecting IDENT or sqlINT

 

The reason behind this is that I need to declare a variable *schema name*, such that I can execute a query in the following way:

 

   declare s varchar(32);

    set s = 'the_schema';

    execute 'select * from ' || the_schema || '.the_table';

 

Please let me know if this is even possible in MonetDB or if you have some tips about that. I tried with a *prepared statement*, as given in MonetDB's documentation -- but the following code cannot execute

 

    prepare 'select * from ' || the_schema || '.the_table';

    because prepare expects an actual query, not a string.

 

I'd like to achieve this with only SQL stored functions. The client I have has to execute the SQL functions directly, and there's no intermediate Java/PHP/etc scripts to build the SQL on the fly before they're being sent to MonetDB server. Thus, I should create a function like so:

 

    create function getData( dataSchema varchar(32) )

    returns bigint

    begin

        declare query varchar(128);

        set query = 'select count(*) from ' || dataSchema || '.the_table';

        return( execute query );

    end;

 

My function is more complicated than this, with other tables and even functions. The issue is that functions belong to one schema, and data tables belong to another schema, which is not known in 'compile' time.

 

Thanks for the help!

 

Luis Ángel