Oracle

Connecting to the Linux server to operate the Oracle database is caused by the on-line access of the project. The on-site data warehouse server does not allow you to directly connect to the Oracle client plsqldev.exe. You can only use commands on

Oracle sets SGA Java code SQL> show parameter sga; name type value comment ----------- comment lock_sga boolean FALSE pre_page_sga boolean FALSE sga_max_size big integer 512 M sga_target big integer 200 m SQL> alter system set sga_max_size = 200 M

Data Inventory flushing process 1. sqlplus/as sysdba2. lsnrctl stop3. shutdown immediate4. startup5. drop user cisadm cascade; 6. create user cisadm identified by cisadm default tablespace cists_01; 7. create and check the directory select * from

Oracle Operation Command --- 1. create a database instance CMD> oradim.exe-new-sid TESTCMD> type initTEST. ora db_name = TESTcmd> sqlplus "/as sysdba" -- 2. choose SQLPLUSsql> startup nomount pfile = initTEST. ora (load the data instance and specify

ORACLE self-study note: in Oracle, the three default users sys change_on_install [as sysdba] system managerscott tiger data dictionary can be used to view the system permissions of the current user. select * from user_sys_privs; select * from

Description of null and NULL in the database: Q: What is null? A: When we do not know the specific data, it is also unknown. We can use NULL. We call it NULL. in ORACLE, the column length containing NULL values is zero. ORACLE allows blank fields of

Using Oracle Data Pump to create an external table 1, Create an external table and generate dump file1, Create a directory and assign related privilege (create any directory) SQL> create directory test as '/home/oracle'; Directory created. SQL>

Common Oracle database query 1. view the SQL code of all users in the current database select username from dba_users; 2. display the SQL code of the current user show user; 3. view the SQL code of all tables in the current database select * from

PL/SQL block definition part-LOB type in earlier versions of Oracle, use the LONG and LONG RAW types to store and enlarge data. Oracle introduced the LOB data type since version 8i, and Oracle recommends that developers use the LOB data type instead

You can use the command line to manually uninstall Oracle Database 11gR2. One is to use DBCA to automatically uninstall the Oracle Database, and the other is to manually uninstall the Oracle Database using the command. The following describes the

Oracle11G time format conversion Code and Test Cases: -- Function to convert a string to a date, or return null if the format is wrong. create or replace function validate_date (p_string in string) return date is begin return to_date (p_string,

When you use DBCA to create an oracle database or delete an existing database of the oracle10g type. The following describes how to create a Database. When creating a Database, you are generally provided with three Database templates (that is, the

The transaction mechanism of the Oracle database is a simple record: con. commit (); The transaction is committed manually. Con. setAutoCommit (true); enables JDBC to automatically commit transactions. Con. rollback (); cancels the submission of

Oracle clears table data here two ways to delete table data in Oracle are introduced: SQL code delete [table name] truncate table [table name] delete to delete table data, the table file will not be cleared. only the unused flag is set. truncate

Oracle 2-single-line function theory and case analysisSQL has two types of functions: single-row and multi-row functions.1. Single Row FunctionsSingle-row functions: operate on Data Objects, accept a parameter to return a result, transform only one

The Time Model for oracle performance optimization collects statistics on the time model. The time model counts the time spent in the database according to the operation type. The most important time model is the database time-DB time, which

Notes for oracle learning-create table stu (id number (6) primary key, // primary key name varchar (20) constraint stu_name_nn not null, // enter sex number (1), age number (3), sdate date, grade number (2) default 1, // The default value is "1"

11g -- statspack install statspack in 11g2, preferably sys user installation. The installation process is as follows: 1. First, create a tablespace for storing the data generated by statspack: create tablespace perfstat datafile

Some common SQL statements that are frequently used in work and learning: create a table: create table [table name] ([automatic number field] int IDENTITY (1, 1) PRIMARY KEY, [Field 1] nVarChar (50) default 'default value 'null, [Field 2] ntext null,

Common Object tables in oracle are the most basic objects in oracle databases. Common tables, partition tables, index tables, and cluster tables can be used to store user data. In an SQL database, user data can be stored in DDL: 1/* 2 create table 3