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in reply to DBI: Identify schema objects for a statement

My first suggestion would be to look in DBD::Oracle and see what it stores in $sth after a prepare(), you may be able to get some information from that. More likely though, you won't. So my next best guess would be do a DESCRIBE and parse its output. That probably won't be satisfactory either. So my third guess is a module I haven't used and isn't Oracle specific but has richer parsing than my SQL::Statement ... DBIx::MyParse an embeddable parser for MySQL which can return data structures of any SQL that MySQL understands.

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Re^2: DBI: Identify schema objects for a statement
by CountZero (Bishop) on Aug 29, 2007 at 13:26 UTC
    But wouldn't that be very MySQL-centric and not necesseraly applicable to an Oracle DB?

    CountZero

    A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

      Well ultimatley, the OP is right in the intuition that "only Oracle can parse oracle" (or somesuch). If there isn't a way for it to do that in a way that returns a data structure containing table and view names, then the OP is left with options that will not be complete so MyParse is my thought on the least incomplete of the options. If the alternative is looking through all the SQL by hand, it would at least allow grabbing a lot of the SQL and setting the rest aside to be looked at by hand so it's a win (this also applies to a lesser extent to SQL::Statement). And too, MyParse is, after all an open source module and can therefore possibly be tweaked to handle more Oraclish dialects (isn't that what the bad guys spoke in LOTR?). You're right, MyParse isn't a good solution but it may be the best perl has to offer for this particular task.

      And Errto - here's anothr possibility: the Mimer SQL folks put out a very credible (non--perl, also non-free IIRC) SQL parser that might also be a possibility.

      update : And here's another thought: the SQL for table and view names is (somewhat) more standard between dialects than other aspects of SQL so errto may be able to get the names out of a partially-parsed structure. E.g given "SELECT foo FROM bar WHERE oracle_only_function(baz) = ?", the parser might be able to tell that the tablename is "bar" even if it barfs on the oracle_only_function().
        with my_alias as ( select * from view1@DBLINK1) select (select * from view27 v27 where v27.col1 = a.col3) from (select * from table1) a, (select * from (select * from my_alias) b, view c where c.fk = b.pk) d where d.fk = a.pk
        Table and view names "more standard"?

        rdfield