IDEA is blocking while a query is executed: this permits from working on other things... To get control back and stop long running Querys, I use TCPView (http://www.microsoft.com/technet/sysinternals/utilities/tcpview.mspx) cutting the underlying tcp-connection... hard but works... It would be nice, if the SQL Query Plugin internaly starts a separete thread for its queries, don´t blocking the whole application. Excellent would be if you provide a button for "java.sql.Statement#cancel" then.