Oracle

To create a table and specify the index table space Sql> CREATE TABLE A1 (a char, constraint PK_A1 primary KEY (a) using index tablespace indx) tablespace users; Table has been created. Sql> Select table_name, index_name, tablespace_name from

Modify the encoding of the data to UTF-8 View and modify Oracle encoding format Method-view Oracle database Character set: Select Userenv (' language ') from dual; Query results: Simplified Chinese_china. Al32utf8 --Modifying the Oracle Database

1. Using SQL statements: This statement is traced using the Toad SQL Monitor tool Select D.status "Status", D.tablespace_name "name", d.contents "Type", d.extent_management "extent Ma Nagement ", To_char (NVL (a.bytes/1024/1024, 0), ' 99,999,990.900

Undo table Space Common operations: (1) View the properties of the Undo table space Undotbs1:Sql> Select b.tablespace_name,autoextensible,retention from dba_tablespaces a,dba_data_files bwhere A.tablespace_name=b.tablespace_name and

Turn from: http://blog.sina.com.cn/s/blog_621a2bdf0100gayl.html When we encounter a class of stored names and procedures that are similar to each other, you can use execute immediate to execute these stored procedures dynamically, and in this

SELECT emp_name, Dept_name FORM Employee, Department WHERE employee.emp_deptid (+) = Department.deptid This SQL text uses a right connection, where the other side of the "(+)" Location is the direction of the connection. (1) Oracle left-Join in

Oracle databases are widely used in different geographies, so it is important for professional Oracle personnel to understand how network connectivity affects database performance. TNS provided by Oracle allows for allocation of traffic in each

1. Basic Grammar SELECT * from table [start and condition] connect by [prior] Id=parentidIt is commonly used to find data that has a parent-child relationship, that is, a tree-structured data, and its return data can clearly differentiate each

1, intersect operationReturn the same part of the query result both their intersectionSql> SELECT * FROM ABC2 intersect3 SELECT * from ABC2;2, minus operationReturns the portion of a row that is not the same as the second query result in the first

Everything has its source, to solve the problem, it has to start from the source, the impact of Oracle performance is very many sources, mainly including the following: Ø Database hardware configuration: CPU,

After you create a synonym, you can access it with SQL, you can also modify the data, but when using this synonym in the stored procedure, the report "table or view does not exist" error, the Internet check, the original to "access to public

Recently, an Oracle-related optimization has been done to a project, from the original 1-minute query time, optimized to only 1 seconds (joint query on 1 million records). In general, the so-called query optimization, mainly to create indexes,

Original source: http://www.blogjava.net/huanghuizz/archive/2006/09/07/68212.html When using the 9205 previous version of the EXP program to export a table with LOB fields to 9205 or more databases, you will encounter an error with the error message

Record Memo View the number of comma occurrences in the string ', 01234,2342,2, ' Sql> Select Translate (', 01234,2342,2, ', ' a0123456789 ', ') from dual; TRANSLATE (', 01234,2342,2, ', ' A0 ------------------------------ ,,,, sql> Select

Take the character type as an example Java code public static void Main (string[] args) throws Exception { String sql = ' Select column_name, data_type, Data_default fr Om user_tab_columns WHERE table_name = ' TEST '; Connection con =

When you create a table today, the fields are enclosed in quotes, and when you select the field you tell the field to find it, as shown in the following example: Sql> CREATE TABLE Test ("id" varchar2); Table created. sql> desc test; Name

The Oracle database file corruption has been resolved. The problem is "error:ora-01033:oracle initialization or shutdown in progress", and then found some information on the Internet, finally with their own practice finally solved, but there is a

1, to determine whether the table exists select count (*) as v_cnt from user_tables where table_name= ' table ' 2, get all the fields in the datasheet Select table_name,column_name from all_tab_columns where table_name = ' table ' 3, creating

first, the introduction Data Warehouse technology is a more mature and widely adopted solution, it is used for all the dispersed raw business data in the whole telecom operation Enterprise, and it can support different departments, different needs

SQL language is divided into four categories: Data Query Language DQL, Data manipulation language DML, data definition language DDL, Data Control Language DCL. It is used to define the structure of the data, such as creating, modifying, or deleting