In message c601fad6-8126-4f43-
b768-62ad6e7ec...@r5g2000yqb.googlegroups.com, Felix wrote:
I want to run a query like
select * from table a, table b where a.foo IN foobar(b.bar)
where foobar is a user function (registered by create_function in
pysqlite3) returning a list of integers.
I am using the Python SQLite3 interface, but the question is probably
general to python and SQL.
I want to run a query like
select * from table a, table b where a.foo IN foobar(b.bar)
where foobar is a user function (registered by create_function in
pysqlite3) returning a list of integers.
Felix wrote:
I am using the Python SQLite3 interface, but the question is probably
general to python and SQL.
I want to run a query like
select * from table a, table b where a.foo IN foobar(b.bar)
where foobar is a user function (registered by create_function in
pysqlite3) returning a
Rewriting the query to say
select * from table a, table b where foobar_predicate(a.foo, b.bar)
would work (foobar_predicate checks if a.foo is in foobar(b.bar). But
it does not allow to use an index on a.foo
Define a function foobar_contains() as follows:
def foobar_contains(foo, bar):
Felix wrote:
Define a function foobar_contains() as follows:
def foobar_contains(foo, bar):
return foo in foobar(bar)
and change the query to
select * from table a, table b where foobar_contains(a.foo, b.bar)
I thought about that (see above), but it would not use an index on
a.foo
On Oct 16, 9:50 am, Felix schle...@cshl.edu wrote:
[snip]
I could create a new table matching each row in b to all values of
b.bar and use that to join but that would be inefficient and very
redundant.
[snip]
Is foobar(b.bar) essentially static? (I'm guessing so if you
considered this as an
