Help!
I need to query a table with an "in" clause, where the SQL looks like this:
select * from some_table where some_field in (?)
I originally took a naive approach and tried this:
in_items = [1,2,3,4]
df = pd.read_sql(MY_SQL_STATEMENT, con=con, params=[in_items]
Which did not work, it throws the following error:
The SQL contains 1 parameter markers, but 4 parameters were supplied
Where I'm stuck at, is figuring out how to pass a list of items as a single parameter.
I can do a string concatenation approach, something like:
MY_SQL = 'select * from tableA where fieldA in ({})'.format(
','.join([str(x) from x in list_items]))
df = pd.read_sql(MY_SQL, con=con)
I would rather avoid this approach if possible. Does anybody know of a way to pass a list of values as a single parameter?
I'm also open to a possibly more cleverer way to do this. :)
Simply string format the placeholders then pass in your params into pandas.read_sql
. Do note, placeholder markers depend on DB-API: pyodbc
/ sqlite3
uses qmarks ?
and most others use %s
. Below assumes the former marker:
in_items = [1,2,3,4]
MY_SQL = 'select * from tableA where fieldA in ({})'\
.format(', '.join(['?' for _ in in_items]))
# select * from tableA where fieldA in (?, ?, ?, ?)
df = pd.read_sql(MY_SQL, con=con, params=[in_items])
For me, using sqllite3, worked this way:
list_of_entries_to_retrive = pd.read_excel('.table_with_entries.xlsx')
list_of_entries_to_retrive = (cell_list['entries']).tolist()
conn = sqlite3.connect('DataBase.db')
queryString = 'SELECT * FROM table WHERE attribute IN (\'{}\');'.format('\',\''.join([_ for _ in list_of_entries_to_retrive]))
df = pd.read_sql(queryString, con=conn)
Do not worked this way:
df = pd.read_sql(queryString, con=conn, params=[list_of_entries_to_retrive]))
Thanks
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