mysql jdbc 驱动程序不支持多语句触发器中的分隔符答案

【问题标题】：mysql jdbc driver does not support delimiters in triggers with multiple statementsmysql jdbc 驱动程序不支持多语句触发器中的分隔符
【发布时间】：2011-03-29 17:57:20
【问题描述】：

我有一些代码由于分号错误而触发了语法错误。如果这是在命令行上运行的，我会用分隔符解决这个问题。不幸的是，jdbc4 驱动程序似乎无法识别分隔符。无论如何要让它运行？

delimiter |
CREATE TRIGGER obs_update BEFORE UPDATE ON obs
FOR EACH ROW
BEGIN
   IF OLD.voided = 0 AND NEW.voided = 1 THEN
      DELETE FROM clinic_obs WHERE id = OLD.obs_id;
   ELSE
      UPDATE clinic_obs SET clinic_obs.revision_token = NOW()
      WHERE NEW.obs_id = clinic_obs.id;
   END IF;
END;
|
delimiter ;

【问题讨论】：

标签： mysql jdbc triggers

【解决方案1】：

尝试删除最后一个 END 字后的分号。所以它看起来像这样：

delimiter |
CREATE TRIGGER obs_update BEFORE UPDATE ON obs
FOR EACH ROW
BEGIN
   IF OLD.voided = 0 AND NEW.voided = 1 THEN
      DELETE FROM clinic_obs WHERE id = OLD.obs_id;
   ELSE
      UPDATE clinic_obs SET clinic_obs.revision_token = NOW()
      WHERE NEW.obs_id = clinic_obs.id;
   END IF;
END|

它应该可以工作，因为我使用 jdbc 驱动程序完成了类似的触发器/过程。

【讨论】：

【解决方案2】：

Delimiter 是 SQL 客户端的命令。 JDBC 中不需要使用分隔符。下面的例子展示了它：

import java.sql.*;

public class TriggerExample {

    public static void main(String args[]) {

        String connectionURL = "jdbc:mysql://localhost:3306/test";
        Connection con = null;

        try {
            Class.forName("com.mysql.jdbc.Driver");
            con = DriverManager.getConnection(connectionURL, "login",
                    "password");
            Statement stmt = con.createStatement();
            stmt.execute("CREATE TRIGGER obs_update BEFORE UPDATE ON obs "
                    + "FOR EACH ROW "
                    + "BEGIN "
                    + "IF OLD.voided = 0 AND NEW.voided = 1 THEN "
                    + "   DELETE FROM clinic_obs WHERE id = OLD.obs_id; "
                    + "ELSE "
                    + "   UPDATE clinic_obs SET clinic_obs.revision_token = NOW() "
                    + "   WHERE NEW.id = clinic_obs.id; "
                    + "END IF; "
                    + "END;");
            con.close();
        } catch (SQLException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (con != null) {
                try {
                    con.close();
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

【讨论】：