java - 更新查询的 SQL 语法错误

Question

我遇到了这个错误。

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: 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 'like = '1', dislike='0', mealID= '17' WHERE mealID ='17'' at line 1 at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) Connection is closed at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:408) at com.mysql.jdbc.Util.handleNewInstance(Util.java:411) at com.mysql.jdbc.Util.getInstance(Util.java:386) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1054) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4120) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4052) at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2503) at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2664) at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2809) at com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1811) at com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1725) at OOADPJdb.database.DBController.updateRequest(DBController.java:73) at projPackage.Menu.updateLike(Menu.java:409) at projPackage.RetrieveMenuUI.likeBtnActionPerformed(RetrieveMenuUI.java:433) at projPackage.RetrieveMenuUI.access$500(RetrieveMenuUI.java:21) at projPackage.RetrieveMenuUI$6.actionPerformed(RetrieveMenuUI.java:276) at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2022) at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2346) at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402) at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259) at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252) at java.awt.Component.processMouseEvent(Component.java:6527) at javax.swing.JComponent.processMouseEvent(JComponent.java:3321) at java.awt.Component.processEvent(Component.java:6292) at java.awt.Container.processEvent(Container.java:2234) at java.awt.Component.dispatchEventImpl(Component.java:4883) at java.awt.Container.dispatchEventImpl(Container.java:2292) at java.awt.Component.dispatchEvent(Component.java:4705) at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4898) at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4533) at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4462) at java.awt.Container.dispatchEventImpl(Container.java:2278) at java.awt.Window.dispatchEventImpl(Window.java:2739) at java.awt.Component.dispatchEvent(Component.java:4705) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:746) at java.awt.EventQueue.access$400(EventQueue.java:97) at java.awt.EventQueue$3.run(EventQueue.java:697) at java.awt.EventQueue$3.run(EventQueue.java:691) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:75) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:86) at java.awt.EventQueue$4.run(EventQueue.java:719) at java.awt.EventQueue$4.run(EventQueue.java:717) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:75) at java.awt.EventQueue.dispatchEvent(EventQueue.java:716) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93) at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

这是我的SQL语句

dbQuery = "UPDATE menu SET like = '" + this.like + "', dislike='" + this.dislike + "', mealID= '" + this.mealID + "'";

dbQuery = dbQuery + " WHERE mealID ='" + this.mealID + "'";

很确定这是正确的，但它不起作用。

Answer 1

在我看来，问题在于对列名使用保留关键字 LIKE，这始终不是一个好主意。