FAQs about ORACLE Database Application Development
FAQs about ORACLE Database Application Development
The ORACLE tutorial is: FAQs about ORACLE database application development and troubleshooting. Hardware Platform: SUN Ultra Enterprise 3000
Operating System: Solaris 2.5 (Simplified Chinese)
Disk: 4.2 GB
Memory: 256 MB
Oracle B version: 7.3.2.1
Installation Directory:/database/oracle (2 GB space under/database)
Installation products: oracle rdbms, SQL * NET, SQL * Plus, Pro * C, Server Manager, etc.
The product is installed properly and runs stably.
Ii. FAQs and troubleshooting in Application Development
ORACLE databases often encounter the following two problems during application development:
1. You cannot close the database using the Shutdown command;
2. The Client Often crashes without reason.
Troubleshooting of Issue 1: as long as the command is correctly used to enable and disable the database (only the Internal user has this permission), problem 1 occurs because the database has not committed transactions, the Shutdown Abort command can be used to close the database, but all uncommitted transactions will be discarded.
Troubleshooting of Issue 2: (1) You can use the Platinum ep m product on the Server to confirm the problem. EMP can be used to monitor system operation. When the Cl ient end crashes, the usage of dml lock will find that due to misoperations, the user will issue a life-and-death LOCK in the database, cause the Client to crash. After determining the process number, go to the ORACLE user and run the 'Kill-9 process no. 'command to release the deadlock and solve the Client-side crash problem.
For example, after the user issues the Update and Delete statements and then runs the Select statement, the user will experience a deadlock.
(2) During application software development? The Client crashes due to some bugs in the application software. At this time, you can use the data dictionary and database base table to search for the data characteristics of the database and the constraints of the database base table to identify the problem as soon as possible, but it has nothing to do with the database performance; of course, you can also monitor the SQL statements that a user is executing on the Server to locate the problem.
For example, when the user data table joins the data, when the application is running, prompts the DUP-VALUE-IN-INDEX and other similar error information, is because the data field of the data base table Primary Key is incorrect, this causes data that should not be added to the database to cause the application to crash. In this case, you can modify the base table and delete the error data to solve the problem.
