Oracle

Methods for detecting bad blocks of Oracle databases: 1, use DBV (DB File Verify) tool; 2, use Rman (Recovery Manager) tool; DBV (DB File Verify) Tool: External command, physical media data structure integrity check; It can only be used for

Rounding (rounding down): Copy Code code as follows: Select Floor (5.534) from dual; Select Trunc (5.534) from dual; The above two usages can be rounded down to the number 5.534, and the result is 5. If you want to take the

1. Pop-up Error Box: Sample code: DECLARE v_count number; Begin Select COUNT (*) into the v_count from dept; If V_count Execution results: 2. Console display: Sample code: DECLARE v_count number; My_exp exception; Begin

The Oracle tutorial you are looking at is: Oracle 8i installation on P4. Method One: 1, copy the Oracle software to the hard disk.2, the hard disk directory file

First, the control documentRole: binary files The structure and behavior of the current instance of the database, the information of the data file log file, and the maintenance of database consistency are recorded. The location and size

Oracle's SUBSTR function simple usage SUBSTR (string, intercept start position, intercept length)//return the intercepted word substr (' Hello World ', 0, 1)//return result is ' H ' * to intercept a string with a length of 1 starting from the

The Oracle tutorial being looked at is the sh file of the Oracle database logical backup. SH file for full backup: exp_comp.sh rq= ' date + '%m%d ' SU-ORACLE-C "Exp System/manager full=y inctype=complete file=/oracle/export/db_comp$rq.dmp" SH

The Oracle tutorial you are looking at is: Oracle Application Experience (1). JAN-1 (January) FEB-2 (February) MAR-3 (March) APR-4 (April) MAY-5 (May) JUN-6 (June) JUL-7 (July) AUG-8 (August) SEP-9 (September) OCT-10 (October) NOV-11 (November) DEC-1

The Oracle tutorial you are looking at is: Oracle quickly deletes duplicate records. When working on a project, when a colleague guides the data, he accidentally makes all the data in a table heavier, that is to say, there is a duplicate of all the

If you want to reprint, please specify the source! (Diao greedy first thanked ...) ） Configuration of Oracle Taf TAF is the abbreviation for transparent application failover, the general application of TAF is in the OPS/RAC environment. Since the

The Oracle tutorial you are looking at is: common problems and exclusions for Oracle database application development. Hardware platform: SUN Ultra Enterprise 3000 Operating system: Solaris 2.5 (Simplified Chinese) Disk: 4.2GB Memory:

Novice Oracle, there will be two big questions: First, index range Scan (scan), second, index unique scan (indexed unique scan), the following two questions through a pictorial way to give you a detailed description: 1, Index range Scan (index

One, the 4 basic characteristics of the business Atomic (atomic):The operations contained in a transaction are considered as a logical unit, and the operations in this logical unit areAll succeed, or all fail. Consistency (consistency):Only

One, add data /* Add Data * * INSERT INTO STU values (' stu0004 ', ' Zhao Yi ', 18,1, "kc0004"); Insert into STU (stu_id,stu_name,stu_age,stu_set) VALUES (' stu0013 ', ' storage 11 ', 19, 1); Note: If you do not specify to add data to

Looking at Oracle data recently, understand the concept of rownum, previously only know the database table for simple additions and deletions to check; After seeing the concept of rownum, it suddenly occurred to me that many business scenarios

1, deletion of primary key ALTER TABLE tablename Drop Primary_key executes the above SQL to delete the primary key, and if it is unsuccessful, ALTER TABLE tablename drop CONSTRAINTS COLUMN CASCADE; --delete constraint ALTER TABLE tablename

In MySQL, we usually use limit to complete the paging operation of DataSet acquisition, while in the Oracle database, there is no such convenient way to implement paging, so we usually finish paging directly in SQL statement, limit. With the help of

INSERT into Table (testcol) VALUES (') The Testcol field, in fact, has been designed to be not null at design time, but we need to understand that NULL and whitespace are different in SQL Server, that is, the above statement inserts an empty, but is

1. Invalid month problem When you recently inserted a time into the database, Oracle reported an "invalid month issue" with the following SQL: Copy Code code as follows: INSERT into Ts_count ( Id,cname, StartTime, Endtime,value ) VALUES (

1. ASCII Returns the decimal number corresponding to the specified character; Sql> Select ASCII (a) a,ascii (a) a,ascii (0) Zero,ascii () space from dual; A A ZERO space --------- --------- --------- --------- 65 97 48 32 2. CHR Give an integer and