Oracle

Oracle-related resources As a developer at the application layer, documents related to SQL in Oracle are certainly not too unfamiliar. We often find out how to use this function, what parameters will be used when creating a table or database, and

Some data formats may be incorrect when basic user data is converted .. For example: 2000-1-1 ==> 2000-01-01, 2000-01-1 ==> 2000-01-01, 2000-1-01 ==> 2000-01-01 I used to write a function/procedure script and a large number of if else scripts..

Dblink Overview A database link is a schema object in one database that enables you to access objects on another database. The other database need not be an Oracle database system. Syntax/writing Create [Shared] [public]

-- Two tables for data copying, the most common copy statement-- Insert into select and select info from-- Select info from cannot be used in Oracle for a simple reason-- Select into is a value assignment statement of PL/SQL language.-- If used,

From the composition of Oracle's SGA, it advocates parameter binding. Using Parameter binding can effectively use the share pool. You do not need to perform hard parsing on cached SQL statements, which can significantly improve performance. The

When importing data to Oracle today, the following message is displayed: Import started on 2008-7-2 8: 51: 15d:/Oracle/ora90/bin/imp. EXE log = C:/docume ~ 1/admini ~ 1/locals ~ 1/temp/1/plsimp. log File = E:/20080630/20070630 .dmp userid = LZ/LZ

RedHat Linux as4 install Oracle 10g (10.2)1. Hardware requirements(1) memory> 1024 MBMemory swap Partition> 1024 MB 2 times memory> 8192 MB 0.75 times memoryDisplay memory commands2)/tmp> 400 m3) detection commandMemory# Grep

Oracle paging query statements can be applied in the format given in this article. Paging Query format: Select * from ( Select a. *, rownum Rn From (select * From table_name) Where rownum ) Where rn> = 21 where the innermost query select * From

When converting an oracle query to an SQL Server, you must be careful about some issues that are not easy to notice. We know that T-SQL is from SQL Server Language The Oracle language engine is PLSQL. ANSI SQL-92 standards are extended to

-- 1: no order by statement. (Most efficient) -- (After testing, this method has the lowest cost. Only one layer is nested, and the speed is the fastest! Even if the queried data volume is large, it is almost unaffected and the speed is still high !)

Several Methods for executing dynamic SQL statements in Oracle In general SQL operations, SQL statements are basically fixed, such:Select T. empno, T. ename from Scott. EMP t where T. deptno = 20;However, dynamic SQL statements may be used in some

The Oracle listening service is registered as a service in windows. Sometimes, the listener cannot be started because of changing the operating system information or other reasons, and the user cannot connect to the Oracle database. If the Oracle

Oracle logminer is a very effective log analysis tool provided by Versions later than 8i. It can obtain the specific content of the log file, such as the DML operation of Oracle, and possibly obtain the SQL statement for transaction rollback, this

For various reasons, Oracle often suffers from Table locking, making operations impossible. First, the System View related to the table lock: A: V $ lock SQL> DESC v $ lock;Name type nullable default

The third log file in the log group is lost due to accidental operations.SQL> Conn/As sysdbaConnected. SQL> startupThe Oracle routine has been started. Total system global area 85006980 bytesFixed size 453252 bytesVariable Size 58720256

[Oracle @ gisdb bin] $./sqlplusError 6 initializing SQL * PlusMessage file SP1 . MSB not foundSP2-0750: you may need to set ORACLE_HOME to your Oracle Software Directory[Oracle @ gisdb bin] $ proBash: Pro: Command not found[Oracle @ gisdb bin]

During Development today, my following requirements: I need to find data from different tables, but the SQL statements are relatively fixed: Select count (*) CNT from table_a where code = codevalue; In the preceding SQL statement, only table_a and

Oracle has two optimization methods when executing SQL statements: Rule-Based RBO and cost-based CBO. The Oracle parameter optimizer_mode determines the optimization method used during SQL coaching. SQL> show parameter optimizer_mode Name type value-

[DB] [Oracle] trigger to create an instance // Trigger name usertotemp Create or replace trigger usertotemp after insert or update or delete On user_info for each row // triggers the following events when operating on the table user_info Declare //

For Oracle DBAs, table space monitoring is an important task of daily and regular monitoring. Table space monitoring includes table space status, data files, table space usage, and remaining conditions. 1. Table space list: SQL> select * from V $