Database Administrator

Create databases/tables in batches using Linux shell The Shell script is as follows: # Create database and table HOST ='Localhost' PORT ='123' USER ='Root' PWD ='' DBNAME ='Top123' TABLENAME ='Gametop800' Mysql_login ='' Mysql_create_db =

You can use the decode function to convert columns in Oracle: If there is A student Table: ID NAME SUBJECT SCORE 1 Zhang San Chinese 90 2 Zhang San Mathematics 80 3 Li Si Chinese

1. Select the most efficient table name order The SQL parser processes the table names in the FROM clause in the order FROM right to left. If the FROM clause contains multiple tables, you must select a table with the least number of records as the

OracleCSService cannot be started: 1. for network connection problems, check the priority of public and private NICs; and check whether the network connection is normal 2. Shared Disk: Check whether the drive letter is set and whether the shared

Oracle locates 1 billion data records: /** The app queries the table and partition where the ID is located by ID, and locates the Stored Procedure for the first 100 table partitions in one table.* Parm id ID* Return table_name table name, par_name

This article does not compare Oracle Spatial with ST_Geometry. For details about the comparison, refer to: here, the data structure and performance comparison are clearly described. In fact, this document shows that OracleSpatial in ArcGIS is

A Date Field in the database has the following data. The SQL statement is as follows: Select age, money, birthday from userinfo Observe carefully that the date field has two formats, one with time and the other without time. In the

I have been using Mysql and Oracle databases for so many years. This time I have to use the C/C ++ language to call the Oracle stored procedure, so I am too lazy to look at the OCI API, I went online to find someone else's encapsulated library, and

The Orcale Data Warehouse command uses exp.exeto restore the Data Warehouse command imp.exe I. Back up the database -- exp Format: exp username/password @ database owner = owner file = C: \ xxx. dmp Eg1: the database TEST is completely exported.

RANK () OVER ([query_partition_clause] order_by_clause) DENSE_RANK () OVER ([query_partition_clause] order_by_clause) You can group and sort the results set of the same group fields by specified fields, Where partition by is the grouping field,

In actual application, multiple insert statements may be executed at a time. I know two ways to share with you: 1. Write the statement block in tools such as PLSQL between begin end, for example: Begin Insert into table values (....); Insert

When the Sequence is defined, if the cache is used, a Sequence jump occurs when the database is closed or down. To solve the sequence disconnection number in the ADF program, make sure that the Oracle database does not generate a disconnection

Error during listener startup [Oracle @ localhost ~] : Lsnctl start TNSLSNR for Linux: Version 10.2.0.4.0-ProductionSystem parameter file is/u01/app/oracle/network/admin/listener. oraLog messages written to/u01/app/oracle/network/log/listener.

The shared pool is mainly composed of data_dictionary that saves the data dictionary and the library cache that saves the SQL and PL/SQL code and execution plan. It also includes several other buffers for different system features and technologies,

Normal equal connections:Select * from a, B where a. id = B. id;This is an internal connection.For external connections:"(+)" Can be used in Oracle, and 9i can use LEFT/RIGHT/full outer join.Left outer join: LEFT OUTER JOINSELECT e. last_name, e.

Some students need to insert images into the table in their projects. The following provides a method for your reference: 1. Create a table. Note: The columns to insert images must be defined as BLOB. Create table image_lob (t_id varchar2 (5) not

Exp_p.sh #! /Bin/sh #$1 generate the storage path of the dmp File If [-d "$1"]; then Echo "" $1 "exist" # The user name/password generated file name is automatically generated based on the date of the day, for example, 20111128.dmp Exp

1. Start the CSS service first # Cd/db/Oracle/product/bin/ #./Localconfig addSuccessfully accumulated necessary OCR keys.Creating OCR keys for user 'root', privgrp 'sys '..Operation successful.Configuration for local CSS has been initialized Adding

A table is the most basic logical unit for storing data in a database. It consists of rows and columns. Oracle divides the table into heap table and index organization table (IOT) and temporary table (temporary table) This section briefly introduces

1. imp user name/password @ Database Name (SID) file = "dmp file path" fromuser = User Name (from which user to export) touser = to which user example to import: Imp public_hmis/public_hmis @ rldm file = d: \ hmis. dmp log = d: \ hmis. log fromuer =