Oracle

In Oracle, use SQL _TRACE to trace SQL Execution. When you execute an SQL statement very slowly, do you want to ask Oracle how to execute this statement? The SQL _TRACE tool provided by Oracle allows you to know exactly what the SQL statements you

First, if it is a large application and the data volume is indeed very large, we recommend that you use ORACLE directly. We do not recommend migrating data from SQL SERVER in the future,Because the migration cost is very high (including the cost of

ORA-01012: not logged on solution conn/as sysdba error ORA-01012: not logged on cause: shutting down the database is not followed by any of the close parameters.Nomal ---> the database can be closed only when all connections are disconnected;

The extension of the oracle insert statement sends a shotgun to a table: (1) insert into table_name [(column [, column...])] select_statement can only insert one table at a time, but the performance is higher than writing multiple insert statements.

The usage of the trunc function is summarized. During this period, the roaming and call data of the previous month will be counted. Use the trunc function. Trunc (datetime [, fmt]); 1. select trunc (datetime, 'yy') from dual; ------------------------

Oracle tool: tkprof Analysis 1 Definition of the executable tool used to analyze the oracle trace file and generate a clearer and more reasonable output result as needed 2 preference [SQL] F: \> tkprof www.2cto.com Usage: tkprof tracefile outputfile

CentOS Oracle 11g R2 is set to boot automatically [1] Change/etc/oratab [root @ localhost ~] # Vi/etc/oratab # This file is used by ORACLE utilities. it is created by root. sh # and updated by the Database Configuration Assistant when creating # a

1. Original data column: mobile phone number, date, quantity 2. decode query result column: mobile phone number, total number in December October 1, and total number in December October 2... Total number of December 2012 select distinct recommender,

The reason why Oracle execution plan does not go through the index is summarized in Oracle Database Operations. Why does one field in a table obviously have an index? When we observe that the execution plan of some languages does not go through the

To split strings in oracle, first create a function to obtain the number of characters to be split. Www.2cto.com create or replace function Get_StrArrayLength (av_str varchar2, -- the string to be split av_split varchar2 -- separator) return number

The RETURNING into statement can be specified in the DML Statement of ORACLE. It is easy to use, and it is not much different from the select into statement. The use of RETURNING statements can simplify PL/SQL programming in many cases. DELETE

Differences between sys and system User Permissions in oracle the most important difference between oracle sys and system users, sysdba and sysoper system permissions, and sysdba and dba roles is the most important difference between sys and system

Common Management of Oracle 11g RAC is in Oracle 11g RAC. The main management tools are srvctl and crsctl. Srvctl (Server Control) is a command line tool used to manage resources defined on the Oracle Cluster Registry (OCR. Www.2cto.com these

Oracle stored procedures with returned values SQL code create or replace procedure sp_pro_order (spName in nvarchar2, spAddress in nvarchar2, spId out number) is begin INSERT INTO ORDER_MC (ID, NAME, ADDRESS, CREATETIME) values (order_id.nextval,

Plsql Export table and Data command Tools-> export tables-> SQL inserts-> create tables. Select other options such as drop and delete under www.2cto.com and select Export file directory export for Export, generate an SQL file, but not an SQL script,

Oracle table lock processing method recently encountered such a problem, operate a table, found that the person is locked, so the query who locked the table, found that many people are locked, security, not all kill, use the following statement to

Tnsnames. ora set up a strange problem to solve the oracle database connection problem that had just been solved for three days. It was really unpleasant to record it. Www.2cto.com needs to connect to the device database of the current network in

Oracle export help [SQL] by entering the IMP command and your username/password, the import operation will prompt you to enter the parameter: www.2cto.com For example: IMP SCOTT/TIGER or, you can control the import running mode by entering the IMP

ORACLE obtains the month list between a certain period of time to obtain the month list between a certain period of time (the example returns the month list between and) www.2cto.com SELECT TO_CHAR (ADD_MONTHS (TO_DATE ('2017-03 ', 'yyyy-mm'),

Oracle Data Block Structure Analysis oracle data block is the smallest unit of database storage, generally N times the operating system block. Its structure is: www.2cto.com block header --> empty row --> data, which is actually a vertical row