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I'm using Sqlite3 database in my Python application and query it using parameters substitution.
For example:

cursor.execute('SELECT * FROM table WHERE id > ?', (10,))

Some queries do not return results properly and I would like to log them and try to query sqlite manually.
How can I log these queries with parameters instead of question marks?

gennad
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  • Looks similar to [this](http://stackoverflow.com/questions/1607368/sql-query-logging-for-sqlite) question, though that example doesn't specify Python. See if it helps. – thegrinner Aug 04 '11 at 13:18

2 Answers2

38

Python 3.3 has sqlite3.Connection.set_trace_callback:

import sqlite3
connection = sqlite3.connect(':memory:')
connection.set_trace_callback(print)

The function you provide as argument gets called for every SQL statement that is executed through that particular Connection object. Instead of print, you may want to use a function from the logging module.

Marcel M
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  • Will that log query info for all queries or just for those of my own app? – TaW Nov 14 '18 at 08:37
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    It’ll log only those queries made through that particular Connection object (`connection` above). I’ve update the answer. – Marcel M Nov 14 '18 at 10:32
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    If you're using the logging infrastructure it's worth noting you can replace "print" with say "logging.debug" seamlessly. – kristopolous May 31 '19 at 07:43
0

Assuming that you have a log function, you could call it first : 

query, param = 'SELECT * FROM table WHERE id > ?', (10,)
log(query.replace('?', '%s') % param)
cursor.execute(query, param)

So you don't modify your query at all.

Moreover, this is not Sqlite specific.

dugres
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