Question

Is it possible to use the with statement in a django queryset? Something like an extra param. I could use .raw, but I was just wondering if this was a way to go (by overriding the Query class possibly or some other route)

For reference, this needs to go before the select statement.

So:

with blah as (select * from table)

select * from blah where blah.column is not null

Answer 1

This is how I did it:

    clone = kwargs.get('clone')
    if clone:
        pre_query = str(clone.query)
        pre_query = pre_query.replace('`','"')
    else:
        qs = clone.get_query_set()
        pre_query = str(qs.query)
        pre_query = pre_query.replace('`','"')

    sql = "\
    with etext as ({pre_query}),\
    words as ( \
    select lower(regexp_split_to_table(element_text , E'\\\\W+')) as word \
    from etext \
    ), \
    word_lex as ( select word, count(*) as cnt,\
    to_tsvector('english', COALESCE(word,'')) as t \
    from words \
    group by 1 order by %s desc ) \
    select * from word_lex WHERE \
    t != '' ".format(pre_query=pre_query)
    limit = kwargs.get('limit')
    order_by = kwargs.get('order_by')
    if limit != None:
        sql += 'limit {limit}'.format(limit=limit)
    if order_by != None:
        sql = sql %(order_by)
    else:
        sql = sql %('cnt')

    return custom_sql(sql)

Basically, I just used the entire sql generated by django to create another with subquery. From there, I used that in the subsequent queries.