Python SQLite how to get SQL string statement being executed

SQLite never actually substitutes parameters into the SQL query string itself; the parameters' values are read directly when it executes the command. (Formatting those values only to parse them again into the same values would be useless overhead.)

But if you want to find out how the parameters would be written in SQL, you can use the quote function; something like this:

import re
def log_and_execute(cursor, sql, *args):
    s = sql
    if len(args) > 0:
        # generates SELECT quote(?), quote(?), ...
        cursor.execute("SELECT " + ", ".join(["quote(?)" for i in args]), args)
        quoted_values = cursor.fetchone()
        for quoted_value in quoted_values:
            s = s.replace('?', quoted_value, 1)
            #s = re.sub(r'(values \(|, | = )\?', r'\g<1>' + quoted_value, s, 1)
    print "SQL command: " + s
    cursor.execute(sql, args)

(This code will fail if there is a ? that is not a parameter, i.e., inside a literal string. Unless you use the re.sub version, which will only match a ? after 'values (' ', ' or ' = '. The '\g<1>' puts back the text before the ? and using '\g<>' avoids clashes with quoted_values that start with a number.)

UPDATE. I learned from this web page that since Python 3.3 you can trigger printing of executed SQL with

connection.set_trace_callback(print)

Should you want to revert to silent processing, use

connection.set_trace_callback(None)

You can use another function instead of print.