Oracle

People who often write SQL statements should know that the main use of the group BY statement is to do subtotals, the following is one of its most common use methods (according to Department, the position of the respective statistical

The existing two Oracle DB is a and B, in order to be able to operate the B database in a database, we need to establish a dblink to B in the a database.Before we create the Dblink, we first check the value of the global_names of DB A (select

Oracle database Import and Export command!Oracle Data Import Export IMP/EXPFunction: Oracle data import and export imp/exp is comparable with Oracle data restore and backup.In most cases, the data can be backed up and restored with Oracle data

There are two types of temporal tables in Oracle, one based on the session, and the data is emptied when a commit occurs, and the data is emptied when the session is disconnected.--transaction-based temporal tablesCreate global temporary table

MyEclipse to import new items insideRight-click >import>general>existing...>next>select root >browse> Project >finishGuide Jar PackageRight-click >properties>java build Path >libraries>ojdbc14-10.2.0.3.jarGet the native IP address cmd>ipconfigThe

Ott is an important tool for accessing object type data in the OCI, which maps object data types or collection types in a database to struct types in C + +. Ott is brought in by Oracle, but the environment variables must be configured before use.

1. Oracle memory is composed of SGA+PGA2. Oracle Database ArchitectureDatabase architecture refers to the composition, working process and principle of database, and the organization and management mechanism of data in database.How Oracle Works:1),

1. Create a data table space:SQL>Create tablespace rusky_data 2 'D:\rusky\rusky_ DATA01,DBF' size 10M 3on 4 Next 10M maxsize 1024m 5 extent management Local, table space created. EXTENT MANAGEMENT LOCAL: Storage area management method.

A: PrefaceRecently decided to summarize the knowledge points every day, and then each week to publish the knowledge points in the classification of the journal.II: The Question(1): In Oracle for age calculation, know that the date of birth after the

Oracle Data Import Export IMP/EXPFunction: Oracle data import and export imp/exp is comparable with Oracle data restore and backup.In most cases, the data can be backed up and restored with Oracle data import and export (no loss of data).Oracle has

In the Oracle OCP exam, a significant portion of the knowledge points involves an examination of common Oracle functions. Although Oracle's Official document SQL Language reference in the functions chapter lists all of the Oracle's own functions,

Attention:After Oracle version 9.2, Oracle's maintenance release number is changed at the second digit bit. And before that is in the third digit digit.1. Major Database Release NumberThe first digit bit, which represents a new version of the

I believe most of them are used People with SQL Server will definitely not get usedto it when they start using Oracle, because the table names and field names that Oracle builds are automatically converted to uppercase. As shown:?????to tell the

Connect by prior recursive algorithm in Oracle--Understandinghttp://blog.163.com/xxciof/blog/static/7978132720095193113752/The connect by prior recursive algorithm in OracleThe start With...connect by prior clause in Oracle uses the connect by as a

1. Wmsys.wm_concat functionConvert columns to rows. Example:-The table data is as follows sql> select * from IDTable; ID NAME---------------------------------------- Ten ab BC CD hi 20 ij The execution

Number: number:38 bit; number (p,s):p: precision, S: Scale (decimal place), in an Oracle database, the Number data type represents numeric type data such as Int,double,float Example: 1234.567 number (6,2)--------> 1234.57 0.001234 Number (2,4)------

Plsql_performance optimization series 14_Oracle High Water Level High Level analysis, plsql14_oracle 2014-10-04 BaoXinjian I. Summary PLSQL _ performance optimization series 14_Oracle High Water Level analysis A high water level line is like a

Oracle global temporary table pitfalls The person in charge at the customer's site called me at a.m. and said it was strange that the downloading feature was slow. This download feature is very complex and I have been optimizing it for a long time.

Oracleblockcorrupt Bad blocks In general, oracle's Bad blocks can be divided into two scenarios: physical damage and logical damage. The physical damage is caused by storage and other reasons. As a result, oracle finds that the checksum of the block

Add and read comments to tables and columns in ORACLE Add and read comments to tables and columns in ORACLE1. Add a comment to the table: SQL> comment on table name is 'table comment "; 2. Add a comment to the column: SQL> comment on column table.