Oracle

--ifelseDECLAREV_num number;  BEGIN v_num: = 100; If V_num > then--elsif v_num > and then--ELSE--END IF; END; --with parameter stored procedure create OR REPLACE PROCEDURE delete_subscriber (p_subid in number) is V_mem VARCHAR2 (+): = ' ';

I remember a colleague asked me this, said the interview before the problem encountered, the following I introduce three ways.First we create a test table here to add the appropriate test data.CREATE TABLE Test (ID number,name varchar (10));INSERT

This is a summary of the recent study of their own experienceI. Oracle's object-orientedSQL is a collection-oriented one that everyone knows, but there is no denying that there are many places in Oracle today that embody object-oriented thinking.

This note will describe the nature and interrelationships of the logical storage structure in the Oracle database server in the segments, regions, and blocks.1. Introduction of data segments, sections and segments2. Overview of paragraphs3. District

First, the indexIndexes are a quick way to access data to improve database performance. Indexing makes it possible for a database program to find the data it needs without having to scan the entire table, like a book's directory, to quickly find the

First, TriggerA trigger is a block of code that executes automatically when a particular event occurs. For example, a record is added to the log table each time an action is made to add or delete an employee table. triggers and stored procedures are

Oracle primary key auto-generated _ table and stored procedure, oracle Stored Procedure -- Create tablecreate table partition (sequence_id VARCHAR2 (36) default sys_guid () not null, sequence_name VARCHAR2 (50) not null, sequence_desc VARCHAR2 (200),

Oracle lock 2: DML operations and locks Oracle automatically acquires row locks and table locks for DML operations. The operation type determines the lock action. The following section summarizes the DML operation locks: SQL Statement

Subquery 3 (use subquery in the from clause), from clause In the FROM clause, subqueries generally return multiple rows and multiple columns, which can be treated as a data table.   Example 1,Query the number, name, location, department count, and

Rowid in Oracle Each table in Oracle has a rowid, which is an 18-character string, for example, AAANgBAABAAAO/KAAA. it contains a string consisting of A-Z, a-z, 0-9, +. yes. Where the A-Z corresponds to 0-25, a-z corresponds to 26-51,0-9 corresponds

OracleGateway11gR2 access to heterogeneous databases (MSSQL) configuration document-graphic details Directory1. Prerequisites 2. Download transparent gateway 3. Unzip and install transparent gateway 4. Configure tnsnames 5. Configure the listener 6.

ORA-04091: table xxxx is mutating, trigger/function may not see it, ora-04091mutating Today, my colleague asked me to see why a trigger always reports an error. When a DML statement is executed to trigger the trigger, a ORA-04091 error is reported:

Oracle creation-stored procedures and functions -- Create a stored procedure Create or replace procedure xxxxxxxxxxx_p (-- Parameter IN indicates the input parameter, -- OUT indicates the output parameter, and the type can be of any legal type IN

Query group statistics (learning notes) and group learning notes Query the total monthly salary of the company. -- Query the total monthly salary of the company. select sum (sal) FROM emp; The maximum wage, minimum wage, and average wage of the

Subquery 2 (Use subquery in HAVING clause), having clause The main function of the HAVING clause is to filter the grouped data. If a subquery in HAVING indicates that grouping filtering is required, data in a single row and a single column is

How to configure the statspack performance report of ORACLE11GADG Create a normal STATSPACK report user on the master database Sqlplus/as sysdbaSQL> @? /Rdbms/admin/spcreate. SQL -- Create an SB userSQL> @? /Rdbms/admin/sbcreate. SQL Then

Postgres function, postgres date function 1. Data restoration is first considered to be performed in the database, but it is not feasible. External applications are considered to be repaired through jdbc. For example, profile_image_url and

Oracle performance optimization operation 15: functional-based index requirements equality matching We have created a function-based index, but if you execute the following query: select * from emp where substr (ename, 1, 1) = 's'; The expected

Guide for installing OracleXE on CentOS Introduction: Installing oracle xe on Centos is mainly used for learning and testing. Although simple, it involves many steps and details. 1. Download Oracle XE Access the

The reason why the oracle task process is not executed after it is submitted /* Run the following command in SQL * Plus */-- check steps when the task is not running -- 1. check whether the instance session is RESTRICTED by select instance_name,