Database Administrator

SQL>SelectTo_char (hire_date, "Color: # ff0000 ;">'Yyyy-MM-dd')FromEmployeesWhereRownum TO_CHAR (HI ---------- 2017-06-21 2000-01-13 1987-09-17 1996-02-17 1997-0 1994-06-07 1994-06-07 1994-06-07 1994-06-07 "Font-family: Arial;

Oracle efficient paging storage process: Create Or ReplacePackage JT_P_pageIs Type type_curIsRefCursor;-- Defines the cursor variable used to return the record set ProcedurePagination (PindexInNumber,-- Index of the number of pages to be

PO --> supply source --> approved supplier list Find the supplier corresponding to the material "105010000056"-> click "properties" to enter the "supplier material properties" form, When "inventory" is set, "supplier delegate" cannot be selected,

We have already installed Ubuntu 11.04. We found that apt-get can only install MySQL 5.1. If you want to use MySQL 5.5, you can only compile it by yourself.The compilation and installation process records are as follows: 1. Go to mysql.com to

Use the cursor and temporary table in the MySQL stored procedure: BEGIN DECLAREC_egidINTEGER; DECLAREDoneINT DEFAULT0; DECLAREMy_testCursorCURSOR FOR (SELECTCp. tb_electricGroup_idFROMTb_chargingPoleASCpWHERECp. tb_chargeStation_id = 12 );

Select trunc (SYSDATE-1, 'Year')-1, 'Year') from dual -- Get first day of last YEAR, sysdate-1 indicate current day in DW case. Select add_months (trunc (sysdate, 'Year'), 12)-(1/86400) from dual -- get the last minute and second of the year. Select

1. query and modify the undo_retention parameter: Run the show parameter undo command to view the current database parameter undo_retention settings. Shown as follows: Undo_management string AUTOUndo_retention integer 10800Undo_suppress_errors

When viewing the SQL Execution Plan, we will find that there are many table connection methods. This article introduces the table connection methods to better understand the execution plan and understand the SQL Execution principles. I. Connection

1Syntax 1.1Row-Level Definition   1.2Table-Level Definition       2NOT NULL Row-level definition only. SQL> create table tn0 (a number (4) not null, B varchar2 (20 )); SQL> create table tn1 (a number (4) constraint nn_tn1_a not null, B varchar2 (

1. TRUNC Function 1. TRUNC (for dates) The date value intercepted by the TRUNC function for the specified element.The syntax format is as follows:TRUNC (date [, fmt])Where:Date: A date value.Fmt date format, which is truncated by the specified

Today, PMO issued a task order. After the database was transformed from the sybase system to the Oracle system, 312 entity tables were created for a total of 20 objects, it must be a monkey year, a month, and does not meet the schedule of the

To increase the query speed, generally: 1.Create a primary key for fields that do not need to be deleted; create an index for fields that may be deleted. 2. If you submit 5 million numbers at a time, each of them must be compared with the 90 million

Function: concatenates a column in a specified query SQL statement into a string separated by a specified character. Deficiency: because the return value of the function is varchar2, And the commonly concatenated string is used to query SQL (because

When using spfile, you can use the v $ parameter. ISSYS_MODIFIABLE field to determine the initialization parameters that can take effect without restarting. V $ parameter. ISSYS_MODIFIABLE parameter Indicates whether the parameter can be changed

One day I met a colleague who asked me to help optimize an SQL statement, which took a long time to run. As a result, I queried the execution plan and found that the SQL was to perform a full table scan. At that time, I checked the definition of the

The role of undo tablespace and redo log files in Oracle is very important. This article focuses on the role and features of undo rollback segments, and briefly introduces the differences between undo and redo and their respective roles: 1. Features

[Root @ rac1 ~] #/Etc/init. d/Oracleasm configureProcessing the Oracle ASM library driver. This will configure the on-boot properties of the Oracle ASM libraryDriver. The following questions will determine whether the driver isLoaded on boot and

The database instance is disabled.Startup nomount database instance starts to the First Stage (Steps:1. Search for the parameter file spfile . ora. If no, search for spfile. ora. If no, find init . ora.2. Allocate SGA3. Start the background process4.

(1) multiple databases can be configured in Oracle, and only one listener can be enabled. You only need to configure the corresponding service name (for example) for multiple databases to connect. Note the following points:1. generally, if multiple

Run the following command Sqlplus/as sysdba Create tablespace test datafile '/data/test01.dbf' size 10240 M; Quit; EOF Run the ps-ef | grep sqlplus command to obtain the process id of the Command executed above: 12345 (1) v $ process If the