java - How to monitor particular column in database

Question

I have an Oracle Database and I want to monitor a particular table/column in the DB . If the column value crosses threshold value I want to call my java application code to perform some operation LIKE EXAMPLE SCALE UP OR SHUTDOWN. How can I achieve this? Any pointers or help needed.

Answer 1

Set Serverout On
Declare
comm Varchar2(2000);
Begin
comm := OSCommand_Run('/home/jguy/runJavaApp.sh')--for calling commands
DBMS_OUTPUT.Put_Line(comm);
End;

Answer 2

您可以使用将在某些条件下执行特定函数/存储过程的触发器（在本例中为更新触发器）。

Answer 3

I suggest you to use triggers, they are designed to do stuff like this and I really wouldn't mess up it with Java in this case.

Answer 4

有多种方法可以做到这一点：

1. 在表上触发，它将检查每个 DML 语句的列值以及值是否超过阈值。

2. 由于触发器可能对表有一些性能影响，您可以创建一个调用存储过程的调度程序作业，该存储过程将定期（每分钟或您喜欢的任何内容）调用，然后检查列值并在超过阈值时调用 java 应用程序。

我更喜欢触发器，但检查对表的性能影响。