How to put parameterized sql query into variable and then execute in Python?

Here is the call signature for cursor.execute:

Definition: cursor.execute(self, query, args=None)

    query -- string, query to execute on server
    args -- optional sequence or mapping, parameters to use with query.

So execute expects at most 3 arguments (args is optional).
If args is given, it is expected to be a sequence.
so

sql_and_params = "INSERT INTO table VALUES (%s, %s, %s)", var1, var2, var3
cursor.execute(*sql_and_params)

is not going to work, because

cursor.execute(*sql_and_params)

expands the tuple sql_and_params into 4 arguments (and again, execute only expects 3).

If you really must use

sql_and_params = "INSERT INTO table VALUES (%s, %s, %s)", var1, var2, var3

then you’ll have to break it apart when feeding it to cursor.execute:

cursor.execute(sql_and_params[0],sql_and_params[1:])

But I think it feels much more pleasant to just use two variables:

sql = "INSERT INTO table VALUES (%s, %s, %s)"
args= var1, var2, var3
cursor.execute(sql, args)

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