Ok, so I have a function that selects certain rows in a sqlite database based on input from a plugin. I got the plugin to select and fetch rows when just one statement is involved, but since I want to add some flexibility to this, I tried making the function use executemany when encountering lists 开发者_高级运维or tuples. Yet, despite all the things I have fiddled and changed, I a still unable to get this to work, either because the sqlite statement is treating each character in the string as a binding, or because there are too many bindings in the tuple. Here's the code I have so far:
def readoffset(self,offset):
vartype = type(name)
print(vartype)
if vartype == int:
self.memcursor.execute('''select all id,matbefore,matafter,name,date
from main as main where id = ?''',[offset])
undolist = self.memcursor.fetchall()
print(undolist)
return(undolist)
elif vartype == tuple or list:
print(vartype)
self.memcursor.executemany('''select all id,matbefore,matafter,name,date
from main as main where name = (?)''', [offset])
undolist = self.memcursor.fetchall()
return(undolist)
Look at http://www.python.org/dev/peps/pep-0249/
Use of this method for an operation which produces one or more result sets constitutes undefined behavior, and the implementation is permitted
So, executemany can be used for INSERT's and UPDATE's but not for SELECT
You can try following code:
elif isinstance(offset, (tuple, list)):
offsets=', '.join(offset)
self.memcursor.execute('''select all id,matbefore,matafter,name,date
from main as main where name IN (?)''', [offsets])
I don't think you need executemany
here.
Try something like this instead:
self.memcursor.execute('''SELECT id, matbefore, matafter, name, date
FROM main
WHERE name IN (%s)''' %
','.join('?'*len(offset)), (offset,))
Note that the string interpolation is done to place multiple placeholders into the query.
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