Database Administrator

I. Operation of sysdate function 1 and sysdateAddition Select sysdate, add_months (sysdate, 12) from dual; -- add 1 year Select sysdate, add_months (sysdate, 1) from dual; -- add January Select sysdate, to_char (sysdate + 7,'Yyyy-mm-dd HH24:

Obtain the DataSet value by page in Oracle.Example:/// /// Obtain the Colletion paging data/// Public DataSet GetList (int PageIndex, int PageSize, string sortExpression, string strWhere){StringBuilder sb = new StringBuilder ();Sb. Append ("select *"

1: Windows platform, because the Windows operating system uses the gb2312 character by default, while mysql uses latin1 for the client and server by default during installation, this leads to a mismatch between character set and character

1. Compile the RHEL5.4 Kernel1.1 install software packages Use the yum or rpm command to install the following software package: Gcc-4 .*Gcc-c ++-4 .*Rpm-4 .*Rpm-build-4 .*RedHat-rpm-config-8 .*Unifdef-1 .*Subversion-1 .* 1.2 install the kernel

View all user partition tables and partition policies (level 1 and level 2 partition tables are included ): SELECT p. table_name AS table name, decode (p. partitioning_key_count, 1, 'Primary partition') AS partition type,P. partitioning_type AS

The standby Construction Method for a RAC is basically the same as that for a single node. we can regard RAC as a single node database and only need to ensure that the logs of all nodes can be transmitted to the slave database. 1. Install Oracle

Select a row of records in the Table: (understanding: rownum is the number of rows sequentially allocated from the query returned by the Oracle System)Select * from (select rownum a, t. * from testtab t) where a = 2;Select * from (select rownum a, t.

The actual instance: Today, I found that the website data was abnormal. I checked the database and encountered the following error when operating a table (tbl_test: Table '. \ mydb \ tbl_test' is marked as crashed and shoshould be retried red You

Environment:Rhel-server-5.5-i386-dvd #! /Bin/bashEcho "kernel. shmall = 2097152">/etc/sysctl. confEcho "kernel. shmmax = 2147483648">/etc/sysctl. confEcho "kernel. shmmni = 4096">/etc/sysctl. confEcho "kernel. sem = 250 32000 100 128">/etc/sysctl.

Part 1: Environment Configuration 1. Install CentOS 5.5 When installing CentOS 5.5, if the server is only running the Oracle database, you must install gnome, development kit, and Legacy development kit when installing CentOS. You can choose not to

Install_mysql_CentOS5.6Conclusion: in fact, the answer is always in front of us, but we are always easy to ignore them. I thought, quietly, and the answer is there.1. download mysql-5.1.56.tar.gz to/opt/src2. $ cd/opt/src3. $ tar-zxvf

SQL * PLUS allows you to create a login. SQL file. This script is executed every time SQL * PLUS is started. In addition, you can create an SQLPATH environment variable. In this way, no matter which directory the login. SQL script is located, SQL *

First, we will introduce how to convert rows into columns, Oracle row-to-column conversion is common. Common examples on the Internet are as follows: Grades table: Student subject grade Student1 language 80 Student1 mathematics 70 Student1 English 60

In the morning, the Provincial Social Security Project Team responded that the database had a system-type SQL statement, which occupied a lot of resources and seriously affected the database performance. The specific SQL statement is: Select count (

ServerDELL R410 2Cpu inter E5620. 4 GHz 12M4CMEM 64GDISK 300 GBMemoryDS3512DISK 600G * 12 RAID5(Because JS is shoddy, it took a month to solve the problem on the server fiber optic card.Problem:1. storage cannot be found on the server from time to

When importing data in half, the disk space is insufficient. This requires that the data of the database files be moved to another disk. 1. offline data files: SQL> alter database datafile 2 'H: \ Oracle \ product \ 10.2.0 \ oradata \ lhoms \ pub \

NEXT_DAY (date, char): returns the date of the first day of the week (specified by char) after the specified date (specified by date). char can also be 1 ~ Replace 7. 1 indicates Sunday. Duzz $ scott @ orcl>SelectSysdate, to_char (sysdate,'Day')

Write a test program when using C in Linux to operate MySQL database IntMain (Void) { MYSQL m_mysql; Mysql_init (& m_mysql ); Const CharPLocalhost [] ="Localhost"; Const CharPUser [] ="Root"; Const CharPPass [] ="123456";

We all know that date and timestamp are both expressions of date and time, but the two types of precision are different. The former is accurate to seconds, and the latter is accurate to decimal seconds (Fractional_seconds_precision), which can be0

In Oracle, we all know that the two single quotes are character-type, But how should we write single quotes in a script. Of course, you can use '''' (four single quotes) to assemble a single quotation mark. In plsql, how do you update text