创建事件以删除 table 中的记录
Creating event to delete records in the table
我正在尝试让我的 mysql 事件正常工作,但我遇到了一个问题,即在没有 autoDelete
事件的情况下创建总线 table,而且我没有收到任何错误.我通过在 sql 浏览器中执行这条语句 show events
在 phpmyadmin 中检查了我的 table 我得到的结果是 empty results
正如我所说的总线 table 在那里? !
我在 phpmyadmin sql 浏览器中检查了 EVENT 语法代码,它有效吗?
DatabaseMetaData dbm = con.getMetaData();
ResultSet tables = dbm.getTables(null, null, "bus", null);
if (tables.next()) {
// here if the table exist just update data. I have the most of my code her.
return status;
} else {
// Create bus table
stt.execute("CREATE TABLE IF NOT EXISTS bus"
+ "(id INT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY,"
+ "mac VARCHAR(30) NOT NULL UNIQUE,"
+ "route int(11) NOT NULL,"
+ "latitude FLOAT(10,6) NOT NULL,"
+ "longitude FLOAT(10,6) NOT NULL,"
+ "created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP)");
stt.execute("CREATE EVENT AutoDelete"
+ "ON SCHEDULE AT CURRENT_TIMESTAMP + INTERVAL 3 MINUTE "
+ "DO "
+ "DELETE FROM bus WHERE created_at < (NOW() - INTERVAL 3 MINUTE)");
insert_update_data(mac, route, latD, longD, con);
return status;
}
尝试在事件名称
后加上 space
"CREATE EVENT AutoDelete "
我认为您的代码当前正在创建一个如下所示的字符串:
CREATE EVENT AutoDeleteON SCHEDULE AT CURRENT_TIMESTAMP + INTERVAL 3 MINUTE DO DELETE FROM bus WHERE created_at < (NOW() - INTERVAL 3 MINUTE)
虽然我很惊讶这没有抛出 SQLException
我正在尝试让我的 mysql 事件正常工作,但我遇到了一个问题,即在没有 autoDelete
事件的情况下创建总线 table,而且我没有收到任何错误.我通过在 sql 浏览器中执行这条语句 show events
在 phpmyadmin 中检查了我的 table 我得到的结果是 empty results
正如我所说的总线 table 在那里? !
我在 phpmyadmin sql 浏览器中检查了 EVENT 语法代码,它有效吗?
DatabaseMetaData dbm = con.getMetaData();
ResultSet tables = dbm.getTables(null, null, "bus", null);
if (tables.next()) {
// here if the table exist just update data. I have the most of my code her.
return status;
} else {
// Create bus table
stt.execute("CREATE TABLE IF NOT EXISTS bus"
+ "(id INT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY,"
+ "mac VARCHAR(30) NOT NULL UNIQUE,"
+ "route int(11) NOT NULL,"
+ "latitude FLOAT(10,6) NOT NULL,"
+ "longitude FLOAT(10,6) NOT NULL,"
+ "created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP)");
stt.execute("CREATE EVENT AutoDelete"
+ "ON SCHEDULE AT CURRENT_TIMESTAMP + INTERVAL 3 MINUTE "
+ "DO "
+ "DELETE FROM bus WHERE created_at < (NOW() - INTERVAL 3 MINUTE)");
insert_update_data(mac, route, latD, longD, con);
return status;
}
尝试在事件名称
后加上 space"CREATE EVENT AutoDelete "
我认为您的代码当前正在创建一个如下所示的字符串:
CREATE EVENT AutoDeleteON SCHEDULE AT CURRENT_TIMESTAMP + INTERVAL 3 MINUTE DO DELETE FROM bus WHERE created_at < (NOW() - INTERVAL 3 MINUTE)
虽然我很惊讶这没有抛出 SQLException