Question

I have a function with a new improved version of the code for automatic table indexing:

def update_tableIndex(self,tableName):
    getIndexMySQLQuery = """SELECT numberID
    FROM %s;""" % (tableName,)

    updateIndexMySQLQuery = """UPDATE %s 
    SET numberID=%s WHERE numberID=%s;""" % (tableName,)

    updateIndex=1
    self.cursorMySQL.execute(getIndexMySQLQuery)
    for row in self.cursorMySQL:
        indexID = row[0]
        self.cursorMySQL.execute(updateIndexMySQLQuery,(updateIndex,indexID))
        updateIndex+=1

While the query ‘getIndexMySQLQuery’ works fine with this syntax, the other one ‘updateIndexMySQLQuery’ doesn’t work.

Any hints or suggestion how to get that fixed?

All comments and suggestions are highly appreciated.

Answer 1

Second one doesn’t work, because you are using three placeholders inside the query string and provide only one variable for interpolation.

updateIndexMySQLQuery = """UPDATE %s 
SET numberID=%%s WHERE numberID=%%s;""" % (tableName,)

This way the string formatting mechanism doesn’t expect you to provide 3 values, as the percent signs are “escaped” (shame on me for the first version of the answer).