Oracle

I used to take notes when I was studying oracle. When I started to read my computer today, I suddenly felt a little unfamiliar. It was a pity to delete it. I didn't delete it on my computer and didn't read it again, therefore, you should review it

This is a relatively biased knowledge, but it has a lot of practical significance and can help DBAs complete some daily management work, for example, you can disable some user functions (prohibit users from modifying or deleting a table, and

ORACLE-based application systems have many performance problems, which are caused by poor SQL Performance of application systems. Therefore, SQL Performance optimization is very important, to analyze and optimize the performance of an SQL statement,

Summary of oracle stored procedures and the use of ref cursor: mainly records the knowledge about oracle stored procedure, from definition to use. Start with the simplest example and go deeper. At the same time, the use of ref cursor is combined

-- How to Use the grade Table data to update the usertable data (with the associated field userid)Update usertable u set u. grade =(Select g. grade from grade g where g. userid = u. userid ); -- How to generate serial numbers for query result

Purpose: Test the function of disabling the database and deleting the data file.(Back up data files)When the database is started, an error is reported. How can I restore the data file ?? How to restore data files without changing paths and data

View the sid and serial of the current session #: SYS @ ORCL> select sid, serial #, status from v $ session where sid = userenv ('sid '); Sid serial # STATUS ---------------------------- 89 3 ACTIVE View the spid corresponding to the current session:

Essential Oracle statements -- Query table space usageSelect upper (F. TABLESPACE_NAME) "tablespace name ",D. TOT_GROOTTE_MB "tablespace size (M )",D. TOT_GROOTTE_MB-F. TOTAL_BYTES "used space (M )",TO_CHAR (ROUND (D. TOT_GROOTTE_MB-F.

In Windows, Oracle 11g cannot be started normally after a shutdown and cannot be started to the mount state: ORA-03113: end-of-file on communication channel Process ID: 4276 Session ID: 1286 Serial number: 2 Find the trc file of the corresponding

Oracle 11g does not allocate segment to empty tables by default. Therefore, when using exp to export Oracle11g databases, empty tables are not exported. By default, the deferred_segment_creation parameter is TRUE. After the deferred_segment_creation

The data to be accessed by the target SQL statement is generally stored in the table, while the data in the ORACLE access table can be accessed in two ways: one is to access the table directly, and the other is to access the index first, in the back

1. Disable all oracle services. You can disable it in the windows Service Manager;2. Open the Registry: regedit open path:HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Services \ delete all service names starting with oracle in this path. This

I. Definition: The Oracle PL/SQL GOTO statement is a sequential control structure available in Oracle. the GOTO statement immediately transfers program control (called "branching") unconditionally to a named statement label or block label. the

Exists: the condition is true when the subquery returns at least one row. Not Exists: the condition is true if the subquery does Not return any row. In: It is equal to a value In the returned result set of the subquery. Not In: it is Not equal to

1. replace or replace in the create or replace Procedure Stored Procedure Code for oracle to CREATE a stored Procedure with null 2. Replace oracle variables (with the same field name) with the @ variable name. For example, replace user_id with @

Background: The emp table has 14 records: Four records in the dept table: The salgrade table has five records: I. CROSS JOIN) Cross join: there are two types: explicit and implicit, without the ON clause. The returned result is the product of the

Before installation, let me talk about the configuration of my computer: OS: Windows 7 32bit CPU: 3 GHz Memory: 2 GB Desk: 320 GB ========================================================== ========== Next, let's take installing oracle 10 Gb as an

Oracle uninstallation is a relatively troublesome task. Unlike other software, we can easily and quickly uninstall the software according to the uninstallation wizard. Oracle uninstallation involves modifying the registry and restarting the

This blog is intended for beginners and I am also a beginner :) We have successfully installed oracle on our computer, so how can we connect PLSQL developer? What about local oracle? First, we must prepare for the following steps: The following

SQL> show userUSER is "ZHONGWC"SQL>SQL> select * from v $ version;BANNER----------------------------------------------------------------Oracle Database 10g Enterprise Edition Release 10.2.0.5.0-64biPL/SQL Release 10.2.0.5.0-ProductionCORE 10.2.0.5.0