Oracle

1 --Create a table2 Create TablePerson (3Id Number Primary Key,4Namevarchar2( +),5 Birth date6 );7 --Create a sequence8 Createsequence Person_id_seq9Increment by 1TenStart with 1 OneNomaxvalue--do not set the maximum value ANocycle--keep

Learning content:A. Creating A database and table spaceB. Create users and assign permissionsC. Create a data tableI. Creating a database and table space(i) Basic concepts of the SQL language1. ConceptAdvanced Structured Query Language and an

First, the comparison of the original scheme: Trigger/job/snapshot +dblink way, can be synchronized and timed refresh;Two different database servers, from one database server a user to read another database server B under a user's data, can be done

Chen Kocha: http://blog.csdn.net/u013474104/article/details/44279309================1.spring Support for Database interviewWhen we develop the persistence layer. We face a variety of options. For example, use JDBC, Hibernate, Java Persistence API,

I. Using profile to manage user passwordsOverview: Profile is a collection of commands that are password-constrained and resource-constrained, and when a database is established, Oracle automatically establishes a profile called default. When the

I wrote a stored procedure that used features, some features to_date (Datefrom, ' yyyy/mm/dd '). After the discovery data insertion error is performed, the data is inserted into "0001/9/14".Feeling baffled, I don't know why this data, after

One: Recovery of tablesFor mistakenly deleted table, as long as not using purge permanent delete option, then recover from the Flashback table area hope is quite large. The general steps are:1. Query the deleted table from flashback tableSELECT *

Take student table as an example to page out pure SQL pagingSELECT * FROM (SELECT- rownum,a.* from- STUDENT ORDER by Createtime DESC ) A WHERE ROWNUM &L t;=) WHERE ROWNUM >=1;MyBatis Sub-page select * FROM (select a.*,rownum

--View table space Select Tablespace_name,file_id,file_name,round (Bytes/(1024 * 1024), 0) | |  M ' Total_spacefrom dba_data_filesorder by Tablespace_name; --Creating tablespace Create tablespace testlogging datafile '/data2/js/test_01.dbf ' size

1. Set Linux system parametersA. Modify the Linux kernel parametersVi/etc/sysctl.confKernel.shmmax = 1073741824/kernel.shmmax = 1024*1024*ram (M)/2 (at least), that is, the numeric size is half of physical memoryKernel.shmmni = 4096Kernel.shmall = 20

The role of Table spaces:1. Determining the spatial allocation of database entities2. Set the share of the database user's space3. Control the availability of some of our database data4. Backing up and recovering dataHow to create a table space

1. Ordering reasonable query conditionsOracle bottom-up analysis sequence where receipts, from the perspective of optimizing performance. It is suggested that these conditions will be able to filter out a large number of lines written where at the

㈠ Partition Table Technology Overview⑴range Partition① ExampleCREATE TABLE T（... Column Definition ... ）Partition by range (Week_num)(partition P1 values less than (4) tablespace data0,Partition P2 values less than (5) tablespace data1,....);②

in the production environment, we will find:① Index Table Space I/O is very high② "DB file sequential read" Wait event is also higherThis indicates that the whole database system, index read and write operation is more, has become the main

There are parentheses in the program Files (x86) path of the 64-bit Win7 system, and Oracle does not recognize such a path, so there is a problem that the database cannot be connected. So we can copy VS2010 's internal debug Web server

1, the applicable system is different: Bitmap index is suitable for OLAP system, and B-tree index is suitable for OLTP system.2, occupy different storage space: Bitmap index requires only a small amount of storage space, and the B-tree index needs

Usually when the relationship between the structure of the tree processing, this is a very complex thing, we can go through the program code to traverse the parent or child node by layer, the disadvantage is obvious, inefficient, operation

One upgrades today the 10g cluster environment to 10.2.0.5. Download the patch P8202632_10205_linux-x86-64.zip, unzip the installation and run after. Midway Is. Error:I/O ERROR cannt reading or opening file in/tmp/...../temp52Online search for

SQL Execution procedure1. Application Layer-Application SQL request to database2. Database code layer-oracle software parsing and optimizing SQL, managing locks, security, concurrency, etc.3. Memory layer-SGA (data cache), PGA (sort and hash)4. Disk

The time displayed by Oracle SQL Developer includes the time, minute, and second settings. oracledeveloper Oracle SQL Developer is a free integrated development environment developed by Oracle. Oracle SQL Developer is a free, non-open-source