SQL syntax error has occurred - mysql

Question

Here is my simple query:
my $SQLp = "SELECT MAX([PawnPayments].[CreationTimeDate]) as MaxTransDate
FROM [PawnSafeDBCE].[dbo].[PawnPayments]
INNER JOIN [PawnSafeDBCE].[dbo].[PawnPaymentDetails]
ON [PawnPayments[.[PaymentID] = [PawnPaymentDetails].[PaymentID]
WHERE [PawnPaymentDetails].[TicketID[ = '$TicketID'
AND [PawnPaymentDetails].[StoreID] ='$StoreID'
Note that query is written on Perl engine. I keep receiving an error that says:
"You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '[PawnPayments].[CreationTimeDate]) as MaxTransDate:"
I believe the error has to do with the bracket notation, but unfortunately, I am having to use this style due to a poorly constructed 3rd party table. Any help? Am I missing something obvious?
Huge EDIT: The table I am querying is actually on a SQL server, not a MySQL server! My database runs on the MySQL server, but this 3rd party database runs on an older version of Microsoft SQL.

Answer 1

I don't know why you have all those square brackets around your table and column names, but they aren't necessary and they aren't standard SQL. That's what is causing your syntax error.
my $SQLp = "SELECT MAX(PawnPayments.CreationTimeDate) as MaxTransDate
FROM PawnSafeDBCE.dbo.PawnPayments
INNER JOIN PawnSafeDBCE.dbo.PawnPaymentDetails
ON PawnPayments.PaymentID = PawnPaymentDetails.PaymentID
WHERE PawnPaymentDetails.TicketID = '$TicketID'
AND PawnPaymentDetails.StoreID ='$StoreID'";
I'll also add that having variables interpolated in your SQL statement like that is potentially leaving you open to SQL injection attacks. Far better to use bind points in your SQL and use extra arguments to execute to fill in the values (assuming you're using DBI).
my $SQLp = "SELECT MAX(PawnPayments.CreationTimeDate) as MaxTransDate
FROM PawnSafeDBCE.dbo.PawnPayments
INNER JOIN PawnSafeDBCE.dbo.PawnPaymentDetails
ON PawnPayments.PaymentID = PawnPaymentDetails.PaymentID
WHERE PawnPaymentDetails.TicketID = ?
AND PawnPaymentDetails.StoreID = ?";
my $sth = $dbh->prepare($SQLp);
$sth->execute($TicketID, $StoreID);
Update: As Bill Karwin points out in a comment, the database.schema.table syntax makes no sense in a MySQL database. So I think you're a little confused. The error message you are getting definitely mentions MySQL, so you're connecting to a MySQL server, using DBD::MySQL - but perhaps you should be connecting to an MSSQL server instead.
It might be useful if you showed us your database connection code - the call that sets up your $dbh (or equivalent) variable.

Answer 2

You say you are querying a MS SQL database, but the error message clearly says you are using a MySQL database or a MySQL database driver.
If you are querying a MS SQL database, fix your connection string.
If you are querying a MySQL database, use a MySQL-compatible query. MySQL uses backticks to quote identifiers (not square brackets like MS SQL).
[PawnPayments].[CreationTimeDate]
should be
`PawnPayments`.`CreationTimeDate`
Note that your code suffers from injection bugs due to incorrect quoting of value inserted into the SQL query. (It's not good enough just to put quotes around the values!) These can cause your code to fail, and they could make you vulnerable to injection attacks. Fix the quoting, or use replaceable parameters.