oracle sql by example

DESC) T1) T2Order by primary key ASC For example, to retrieve 10 or 20 records from the table sys_option (primary key: sys_id), the statement is as follows:Select *From (select top 20 *From (select top 29 * From sys_option order by sys_id DESC) T1) T2Order by sys_id ASC Oralce database --------------------------------------------------------------------------------Retrieve N records from the M records in the database tableSelect *From (select rown

type conversions to columns when comparing data of different data types.Suppose Empno is an indexed column of a numeric type.SELECT ... From EMP WHERE EMPNO = ' 123 'In fact, after the Oracle type conversion, the statement translates to:SELECT ... From EMP WHERE EMPNO = to_number (' 123 ')Fortunately, the type conversion did not occur on the index column, and the purpose of the index was not changed.Now, suppose Emp_type is an indexed column of a cha

When writing a stored procedure in Oracle, a large SQL statement is sometimes used, but when viewed with the Pl/sql tool test you cannot see the SQL, and the discovery can be handled through an Oracle physical temporary table. Add dbms_output.put_line ('

Common Oracle problems with removing users and tablespaces (for example, a ORA-01940 cannot delete a solution for a currently connected user) at this time enter the sqlplus command window as an administrator. when you delete a user, the following problem sometimes occurs: The ORA-01940 cannot delete the currently connected user. The solution is: 1) view the user's connection status select username,sid,seria

4290 [email protected] (TNS V1 -V3) INACTIVESYS Oracle 4417 [email protected] (TNS V1 -V3) ACTIVEABC Oracle 157 119 4830 [email protected] (TNS V1 -V3) ACTIVEEither kill it in Oracle, kill it under the operating system, and, for a statement with status killed, apply the OS kill command in order to get the most out of it.Alter system kill session ' 153,12 ';Alter

attackers an opportunity to invade, and database vulnerabilities can really threaten your data security. An Huaqin and attack and defense laboratory comprehensive years of database attack and defense experience and accumulation in the following article, the Oracle database with the largest market share is now an example of Oracle's SQL injection threat and some

) connect through tg4msql:1. Copy inittg4msql. ora from the tg4msql \ ADMIN directory in the Oracle main directory and change it to init 2. Configure init ******************************# This is a sample agent init file that contains the HS parameters that are# Needed for the transparent gateway for SQL Server ## HS init Parameters#Hs_fds_connect_info = "Server = biotify; database = salesdata1"Hs_fds_tr

Document directory PL/SQL syntax % Type of Custom Data Type Record of composite data type % Rowtype of composite data type Summary of Oracle Extended Data Types PL/SQL syntax The PL/SQL program consists of three parts: Declaration, execution, and exception handling.Template: Declare/* variable Declaration */begi

Oracle SQL statement Optimization Although orm ing is used in the project, the optimization of the Oracle system is very valuable. Here we will summarize the commonly used statements from the perspective of SQL statements. 1. Optimization in the from field: Oracle installs t

Label:In SQL Server, the number of affected rows returned is: If @ @RowCount In Oracle, the number of affected rows returned is: If sql%rowcount Cases: Sql server: Create procedureproc_test@Stat int=0, @MsgId varchar( -)="', as BEGIN UpdateT_mtSetStat=@Stat, Ostat=@Stat, Rpttime=Getdate()WhereM

Example of how to use the decode function in oracle, oracledecode Decode usage 1: Use decode to determine whether the string is the same DECODE (value, if1, then1, if2, then2, if3, then3,..., else) Meaning:IF condition = value 1 THENRETURN (value 1) ELSIF condition = value 2 THENRETURN (value 2)...... ELSIF condition = value n THENRETURN (value 3)ELSERETURN (default)END IF

Tags: SQL query statement SQL Tutorial SQL language SQL database tutorialOracle SQL Language Query statement-beyond OCP proficient in Oracle video tutorial training 29This course introduces:Oracle Video tutorial, wind Brother this

the success: EXEC master.dbo.sp_addlinkedserver @server = N ' aliases ', @srvproduct =n ' library name ', @provider =n ' Msdaora ', @datasrc =n ' TNS name ' EXEC Master.dbo.sp_addlinkedsrvlogin @rmtsrvname = n ' Alias ', @locallogin = NULL, @useself = N ' False ', @rmtuser = n ' pattern name ', @rmt Password = N ' password 'END 3. Test Query Oracle Database SELECT * FROM OPENQUERY (ora_test, ' SELECT * from tab ')END 4. Iss

Oracle, but the char in Oracle with a maximum length of $ bytes. So your can ' t migrate char (2048) in your SQL Server script to Oracle without any changes, you should use CLOB instead if n > 2000. In Oracle database, char[(size)] Can is also is used in fixed-length charac

parameter to start a job Coordinator background process. With Oracle 10g DBMS_Scheduler this is not needed any more. If you want to user resource plans and/or consumer groups you need to set a system parameter:Alter system set resource_limit = true;Getting started quicklyTo quickly get a job running, you can use code like this: BeginDbms_scheduler.create_job (Job_name => 'demo _ job_schedule', Job_type => 'plsql _ Block', Job_action => 'in in package