Oracle

Students who write SQL frequently may use the two Keywords Union and union all, and maybe you know that they can combine the result sets of two queries. So what's the difference? Below we have a simple analysis. Comparison Union: Distinct The two

Used sequences in triggers (SEQUENCE): Create or replace trigger Tri_supplier before insert on SUPPLIER for each row begin Select Seq_ Supid. Nextval Into:new.supcode from dual; Select Seq_supid. Currval Into:new.supID from dual; End

To_date formatDay:DD Number 12DY abbreviated FriDay spelled out FridayDdspth spelled out, ordinal twelfthMonth:MM Number 03Mon abbreviated MarMonth spelled out MarchYear:YY two digits 98YYYY four digits 1998 24-hour format of the time range: 0:00:00-

The workaround is as follows: 1: Check V$db_object_cache SELECT * from V$db_object_cache WHERE name= ' crm_lastchginfo_day ' and locks!= ' 0 '; Note: Crm_lastchginfo_day is the name of the stored procedure. Found locks=2, 2: Identify the value

' Open the Database Public Sub openoradb () On Error GoTo Toexit Oradb_open = False Set oradb = New ADODB. Connection Oraconstr = "PROVIDER=ORAOLEDB.ORACLE.1; Password= "& Strorapwd &"; User id= "& Strorauser &";D ata source= "& Oradbnetname &";

Oracle Install GuideMemory Requirements:Minimum:1 GB OFRAMRECOMMENDED:2GB of RAM or More#grep Memtotal/proc/meminfoTo view virtual memory space:Df-h/dev/shm/To install a dependency package:Yum install binutils compat-libcap compat-libstdc++ gcc

Oracle Install GuideMemory Requirements:Minimum:1 GB OFRAMRECOMMENDED:2GB of RAM or More#grep Memtotal/proc/meminfoTo view virtual memory space:Df-h/dev/shm/To install a dependency package:Yum install binutils compat-libcap compat-libstdc++ gcc

1. Querying all Table spacesSelect Dbf.tablespace_name,Dbf.totalspace " Total (M)",Dbf.totalblocks as total block number ,Dfs.freespace " Total remaining (M)",Dfs.freeblocks " number of remaining blocks ",(dfs.freespace/dbf.totalspace) * " idle

Citation Link: http://blog.csdn.net/w183705952/article/details/7367272The second: The growth strategy for setting the ID is native, but you need to create a globally used sequence named Hibernate_sequence (the name is the default sequence name of

Open Navicat----->oci options Right--Select Oci.dll pathBy default in the Navicat installation directory there is a instantclient folder directly select the inside of the OCI.LL can beMy navicat is 11.1.10 64-bit instantclient is

Adding redundant control files is naturally a layer of security for the database, after all, the single link control file is a little bit dangerous, after all, is the hub of the library file. Needless to say, into today's theme, for RAC nature can

Xi. Sub-query1. Sub-query OverviewReasons to learn the subqueryExample: Querying employee information with a higher salary than ScottIdea: 1, Scott's salarySelect Sal from emp where ename= ' SCOTT ';2, 3000 higher than the staff informationSELECT *

Purpose: How do I define a base type, reference type, and record type variable in PL/SQL?Define a variable of the base type1 SetServeroutput on ;2 3 --using variables of the base type4 Declare5 --defining basic variable Types6 --defining basic

For loop1 /*2 For Loop printing 1 to ten3 */4 5 SetServeroutput on;6 7 Declare8 9 beginTen forIinch 1..TenLoop One Dbms_output.put_line (i); A - EndLoop; - the End; - /While loop1 /*2 Printing numbers 1 ~ Ten3 */4 5 SetServeroutput on;6 7

Self-summary, welcome fear Turn!The role of restraint is not much to say, directly see how to use it.Non-null constraint:To set a non-null constraint when creating a table:CREATE TABLE table_name (column_name datatype not NULL)To add a non-null

1. View the Oracle configuration information (service_name, SID, Tnsname) in an AIX environment.Sid:Echo $ORACLE _sidSERVICE_NAME:Sqlplus/as Sysdba;Show parameter instance_name;Show parameter service_names;Show parameter service;Select

Original address: http://www.cnblogs.com/gengaixue/archive/2012/11/21/2781037.html1.TRUNC (for dates)The date value that the Trunc function truncates for the specified element.Its specific syntax format is as follows:TRUNC (Date[,fmt])whichDate a

1. Standard SQL specification1, single ifIFV=... Then END IF;2、IF...ELSE IFV=... Then ELSEt ....; END IF; 3, multiple ifIFV=... ThenElsif v=... Thent ...; ENDIFL Note: multiple if is'elsif'No'ELSE IF'2. Decode functionDECODE

One, Oracle 11gThe automatic collection of statistics data is available in the 11g version of Oracle. One of the steps in deploying 11g Oracle software during deployment is to prompt for the ability to start this feature (which is enabled by default)

1, first look at the C:\Windows\assembly directory is not only a oracle.dataaccess, my version is 10, if there is only one, then look down;2, the complete Odp.net (directory contains registration files) copied to the C drive, and then CMD to the Odp.