I'm creating a table of descriptions from a list of not necessarily unique descriptions. I would like the table to contain only distinct descriptions, so while inserting descriptions into the table, I need to check to see if they already exist. My code(simplified) looks something like as follows:
cur.execute(''' CREATE TABLE descriptions
(id INTEGER PRIMARY KEY AUTOINCREMENT, desc TEXT)''')
descripts = ["d1", "d2", "d3", "d4", "d3", "d1", "d5", "d6", "d7", "d2"]
cur.executemany('''
INSERT INTO descriptions(desc)
VALUES (?)
WHERE NOT EXISTS (
SELECT *
FROM descriptions as d
WHERE d.desc=?)
''', zip(descripts, descripts))
The result is OperationalError: near "WHERE": syntax error
, and I'm not sure exactly where I'm going wrong.
Just a note: I realize I could solve this using a set()
structure in python, but for academic reasons this is not permitted.
Thanks
To replace VALUES
by SELECT
should work
cursor.executemany('''
INSERT INTO descriptions(desc)
SELECT (?)
WHERE NOT EXISTS (
SELECT *
FROM descriptions as d
WHERE d.desc=?)''',
zip(descripts, descripts))
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