Question

Here is my existing query which successfully selects distinct records from two tables and combines them into one column:

SELECT index_text AS unique_text FROM words
UNION
SELECT c1index_text FROM words_content 
ORDER BY unique_text

Now I want to eliminate all records WHERE body NOT IN (SELECT body FROM sms) (or NOT EXISTS, whatever works is fine). The problem is that no matter what I try, either I get a syntax error whenever I attempt to use parentheses, or it will not recognize sms.body (even if I precede every column by its parent table). I’m thinking some SQLite limitations may be making this harder than it needs to be, but there has to be a workaround. Below are queries I have tried unsuccessfully (I have also tried numerous variations of these queries to no avail):

SELECT index_text AS unique_text FROM words
UNION
SELECT c1index_text FROM words_content
  WHERE body NOT IN (SELECT body FROM sms)
ORDER BY unique_text

Results in error: No such column: body

SELECT words.index_text AS unique_text FROM words
UNION
SELECT words_content.c1index_text FROM words_content
LEFT JOIN sms
  ON sms.body=unique_text
ORDER BY unique_text

Results in error: No such column: unique_text

How do I join to an alias column and show only records that do not exist in sms.body? Thanks,

Answer 1

If you use where or join clauses in UNIONs you have to apply them to both select statements.

SELECT index_text AS unique_text 
FROM words
where index_text NOT IN (SELECT body FROM sms)
UNION
SELECT c1index_text 
FROM words_content
WHERE c1index_text NOT IN (SELECT body FROM sms)
ORDER BY unique_text