24 lines
884 B
MySQL
24 lines
884 B
MySQL
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--calculate_position()
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----------------------------------------------------------------------------------
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DROP FUNCTION calculate_position() CASCADE;
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CREATE FUNCTION calculate_position() RETURNS trigger AS
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'
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BEGIN
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IF(TG_OP=''INSERT'') THEN
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UPDATE cc_playlistcontents SET position = (position + 1)
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WHERE (playlist_id = new.playlist_id AND position >= new.position AND id != new.id);
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END IF;
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IF(TG_OP=''DELETE'') THEN
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UPDATE cc_playlistcontents SET position = (position - 1)
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WHERE (playlist_id = old.playlist_id AND position > old.position);
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END IF;
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RETURN NULL;
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END;
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'
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LANGUAGE 'plpgsql';
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CREATE TRIGGER calculate_position AFTER INSERT OR DELETE ON cc_playlistcontents
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FOR EACH ROW EXECUTE PROCEDURE calculate_position();
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