character set conversion

execute the script SQL statement in Sqlplus and output the result to the ouput file--save time by turning off console outputSetTermoff;--The executed SQL statement is displayed in the output file againSetEcho on;--shows the time taken to execute

InnoDB The storage Engine implements the online DDL The principle is that when you perform a create or delete operation, the DML The operation log is written to a cache, and the index is created and then re-applied to the table to achieve data

Mysqldump is used to back up a database or to migrate data between different databases, Mydqldump's backup includes SQL statements to create tables and mount tables.First, mysqldump use method(1), back up a single database or some tables in the

The INFORMATION_SCHEMA database is the MySQL system's own database, which provides access to the database metadata. Feeling information_schema is like an encyclopedia of MySQL instances, which records most of the information we need to close in the

Oracle Basic data types (also called built-in data types built-in datatypes) can be categorized by type: String type, Number type, date type, LOB type, LONG raw& RAW type, ROWID & urowid type.Before Apple told the string type, let's talk about

Basic concepts:A character (Character) is the smallest of the ideographic symbols in a human language. such as ' A ', ' B ' and so on;Encoding (Encoding) is given a series of characters, assigning a numeric value to each character, and representing

A problem has recently been addressed because of a hit ORA-600 [kole_t2u], [description], bugs causing a large number of udump files to be dumped in the Cdmp directory,These cdmp then burst the local disk space, triggering ORA-7445 [_MemMove () +64]

On the Internet to check some of the MySQL coding related information, here to tidy up, the wrong place to welcome you to criticize. 1. mysql character set-related variables:-Character_set_server: Default internal operation character

Some simple command comparisons for Oracle and MySQL1) sql> Select To_char (sysdate, ' Yyyy-mm-dd ') from dual;Sql> Select To_char (sysdate, ' Hh24-mi-ss ') from dual;Mysql> Select Date_format (now (), '%y-%m-%d ');Mysql> Select Time_format (now (),

1. Optimize data typeThere are several types of data in MySQL, and if you are a DBA, you are rigorously checking the data types according to the principles of optimization, but developers may choose what they think is the simplest scenario to speed

Some simple command comparisons for Oracle and MySQL1) sql> Select To_char (sysdate, ' Yyyy-mm-dd ') from dual;Sql> Select To_char (sysdate, ' Hh24-mi-ss ') from dual;Mysql> Select Date_format (now (), '%y-%m-%d ');Mysql> Select Time_format (now (),

first, what isOracleCharacter SetThe Oracle character set is a collection of symbols that interpret a byte of data, have a size, and have a mutual containment relationship. ORACLE's support for national language architectures allows you to store,

Oracle Basic Data Type Summary2013-08-17 21:04 by Xiaoxiang Hermit, 5959 reads, 2 Comments, Favorites, compilation Oracle Basic data types (also called built-in data types built-in datatypes) can be categorized by type: String type, Number type,

Some simple command comparisons for Oracle and MySQL1) sql> Select To_char (sysdate, ' Yyyy-mm-dd ') from dual;Sql> Select To_char (sysdate, ' Hh24-mi-ss ') from dual;Mysql> Select Date_format (now (), '%y-%m-%d ');Mysql> Select Time_format (now (),

1. View the database character set?The database server character Set select * from Nls_database_parameters, which is derived from props$, is the character set representing the database.The client character set environment, select * from Nls_instance_

In the operation of MySQL, often need to convert characters into numbers, this step is simple, but not commonly used words are easy to forget, now will be found on the Internet The method is recorded as follows:1. Convert the number of characters to

I. What is the Oracle character setThe Oracle character set is a collection of symbols that interpret a byte of data, have a size, and have a mutual containment relationship. ORACLE's support for national language architectures allows you to store,

Note when using EXPDP and IMPDP: EXP and IMP are client tool programs that can be used either on the client or on the server. EXPDP and IMPDP are tool programs on the server. They can only be used on the ORACLE server, but not on the client. IMP

ORACLE11g IMP-00058 problem today, the boss gave me a task to put four. the dmp file is imported into the oracle10G Database. I installed the 11G database on my local machine. If I didn't want it, I would just export it. Use the import table

The following articles mainly describe five useful methods for MySQL query optimization. Anyone familiar with SQL statements knows that if you want to operate a task, SQL statements can be written in many ways, but the query performance varies with