I am using Python 3.6, pyodbc, and connect to SQL Server.
I am trying make connection to a database, then creating a query with parameters.
Here is the code:
import sys
import pyodbc
# connection parameters
nHost = 'host'
nBase = 'base'
nUser = 'user'
nPasw = 'pass'
# make connection start
def sqlconnect(nHost,nBase,nUser,nPasw):
try:
return pyodbc.connect('DRIVER={SQL Server};SERVER='+nHost+';DATABASE='+nBase+';UID='+nUser+';PWD='+nPasw)
print("connection successfull")
except:
print ("connection failed check authorization parameters")
con = sqlconnect(nHost,nBase,nUser,nPasw)
cursor = con.cursor()
# make connection stop
# if run WITHOUT parameters THEN everything is OK
ask = input ('Go WITHOUT parameters y/n ?')
if ask == 'y':
# SQL without parameters start
res = cursor.execute('''
SELECT * FROM TABLE
WHERE TABLE.TIMESTAMP BETWEEN '2017-03-01T00:00:00.000' AND '2017-03-01T01:00:00.000'
''')
# SQL without parameters stop
# print result to console start
row = res.fetchone()
while row:
print (row)
row = res.fetchone()
# print result to console stop
# if run WITH parameters THEN ERROR
ask = input ('Go WITH parameters y/n ?')
if ask == 'y':
# parameters start
STARTDATE = "'2017-03-01T00:00:00.000'"
ENDDATE = "'2017-03-01T01:00:00.000'"
# parameters end
# SQL with parameters start
res = cursor.execute('''
SELECT * FROM TABLE
WHERE TABLE.TIMESTAMP BETWEEN :STARTDATE AND :ENDDATE
''', {"STARTDATE": STARTDATE, "ENDDATE": ENDDATE})
# SQL with parameters stop
# print result to console start
row = res.fetchone()
while row:
print (row)
row = res.fetchone()
# print result to console stop
When I run the program without parameters in SQL, it works.
When I try running it with parameters, an error occurred.
Parameters in an SQL statement via ODBC are positional, and marked by a ?
. Thus:
# SQL with parameters start
res = cursor.execute('''
SELECT * FROM TABLE
WHERE TABLE.TIMESTAMP BETWEEN ? AND ?
''', STARTDATE, ENDDATE)
# SQL with parameters stop
Plus, it's better to avoid passing dates as strings. Let pyodbc take care of that using Python's datetime:
from datetime import datetime
...
STARTDATE = datetime(year=2017, month=3, day=1)
ENDDATE = datetime(year=2017, month=3, day=1, hour=0, minute=0, second=1)
then just pass the parameters as above. If you prefer string parsing, see this answer.