问题
I am trying to fetch "bar_ids" from "foo" table using mysql-python. To this end, I got the following error and I am receiving only few bar_ids. How do I get this correctly without warning error?
My table is shown below:
create table foo (foo_id int, bar_id int, foo_name varchar(255))
My query & Error:
foo_ids = 16600, 16602, 16607, 16609, 16611, 16613
Warning: Data truncated for column 'bar_id' at row 1
cursor.execute("""select bar_id from foo where foo_id in (%s)""", (foo_ids,))
Warning: Truncated incorrect DOUBLE value: '16600, 16602, 16607, 16609, 16611, 16613'
cursor.execute("""select bar_id from foo where foo_id in (%s)""", (foo_ids,))
回答1:
This question has been asked before in SO. Putting in a response so it might help to give some context and help @brisk read this sort of error going forward.
The problem is that it is taking 'foo_ids' as a string and not as individual values. So it's essentially trying to run:
select bar_id from foo where foo_id in ('16600, 16602, 16607, 16609, 16611, 16613')
Notice the quotes? You want it to run:
select bar_id from foo where foo_id in (16600, 16602, 16607, 16609, 16611, 16613)
so when you reported your error, it included 'quotes' around the numbers.
There are a few solutions that you can consider.
回答2:
Basically, you need to re-create the param list yourself:
param_list = '%s,' * (len(foo_ids) - 1) + '%s'
sql = """select bar_id from foo where foo_id in (%s)""" % param_list
cursor.execute(sql, foo_ids)
来源：https://stackoverflow.com/questions/28583706/python-warning-truncated-incorrect-double-value