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Another way would be to use EXCEPT like this: SELECT u.id AS user_id, s.id AS song_id FROM users AS u CROSS JOIN songs AS s EXCEPT SELECT user_id, song_id FROM songs_played ; The result would be all u.id, s.id pairs that are not found in songs_played.


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You can use not exists clause to do this. SELECT u. ID AS user_id, s. ID AS song_id FROM songs s, users u WHERE NOT EXISTS ( SELECT 1 FROM user_songs us WHERE us.user_id = u. ID AND us.song_id = s. ID ) ORDER BY 1, 2


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SQLite is an embedded database, so it does not run as a separate process; it's just a library used by some other language/framework. Both Djano (actually, Python) and Android do indeed embed SQLite. Any Django website automatically supports SQLite.


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Hi You can use Free hosting plan form hostinger Here is the list of free hosting feature : http://www.free-web-hostings.info/tag/sqlite/ Here is the company website : http://www.hostinger.co.uk/ I thing this will help to you.


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This is a well known "quirk" of SQLite. SQLite uses what it calls a dynamic typing system, which ultimately means that you can store text in integer fields - in Oracle, SQL Server and all the other big hitters in the database world, attempts to do this will fail - not with SQLite. Take a look here: SQLite uses a more general dynamic type system. In ...


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You should remove the: ORDER BY e.journal_year DESC part, since it does not change the result of the query, but only slows down its execution. Another possibility is to rewrite the query by using a join instead of a IN: SELECT DISTINCT t.a FROM titles t JOIN erpubtbl e ON e.id = t.a JOIN abstract_mesh am ON am.pmid = e.pmid JOIN mesh_descriptor md ON ...


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The abstract_mesh table has no index. As this EXPLAI QUERY PLAN output (from SQLite 3.8.10.2) shows, searching in this table is so slow that it is worthwhile to create a temporay index as part of the execution of the query: 0|0|0|SCAN TABLE titles AS t VIRTUAL TABLE INDEX 3: 0|0|0|EXECUTE LIST SUBQUERY 1 1|0|2|SEARCH TABLE mesh_descriptor AS md USING ...


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With the default settings, when rows (or entire tables) are deleted, SQLite does not remove empty pages from the database file. (This setting can be changed with PRAGMA auto_vacuum.) In most cases, keeping empty pages in the database file is good idea because they will be reused by new rows that are inserted later, and adjusting the database file to remove ...



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