GUACAMOLE-926: Disable batch executor for SQL Server JDBC extension - it doesn't work.

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-sqlserver/src/main/java/org/apache/guacamole/auth/sqlserver/conf/SQLServerEnvironment.java

@@ -295,6 +295,21 @@ public class SQLServerEnvironment extends JDBCEnvironment {
                 true);
     }
 
+    @Override
+    public boolean shouldUseBatchExecutor() {
+
+        // The SQL Server driver does not work when batch execution is enabled.
+        // Specifically, inserts fail with com.microsoft.sqlserver.jdbc.SQLServerException:
+        // The statement must be executed before any results can be obtained.
+        // See https://github.com/microsoft/mssql-jdbc/issues/358 for more.
+        logger.warn(
+                "JDBC batch executor is disabled for SQL Server Connections. "
+                + "Large batched updates may run slower."
+        );
+        return false;
+        
+    }
+
     /**
      * Returns true if all server certificates should be trusted, including
      * those signed by an unknown certificate authority, such as self-signed