how to use dblink in oracle sql

TableinWhere NOT EXISTS (SELECT * from Tablein where Tablein.aid = 7)The use of exists and in efficiency, usually using exists is higher than in efficiency, because in does not walk the index, but depends on the actual use of:In the case of large appearance and small inner table, exists is suitable for small appearance and large inner table. -----------------------------------------------------------------

Tags: Oracle monitoringToday, my colleague even my computer is not even, and asked me to listen to open, and finally because the monitoring does not match,Resolving documents 1. Modify the file G:\app\eric\product\11.2.0\dbhome_1\NETWORK\ADMIN\listener.ora fileLISTENER =(Description_list =(DESCRIPTION =(ADDRESS = (PROTOCOL = IPC) (KEY = EXTPROC1521))(ADDRESS = (PROTOCOL = TCP) (HOST = localhost) (PORT = 1521))(ADDRESS = (PROTOCOL = TCP) (HOST = 192.16

1.%type DECLARE dname DEPT. Dname%-- dynamically defines the type of variable that changes with the type of Dname field in the Dept Table . BEGIN SELECTinto fromWHERE DEPTNO=; Dbms_output. Put_Line (dname); END ; 2.%rowtypeDECLARE v_row DEPT%-- and each column data type in the DEPT table is the same drop BEGIN SELECT * into from WHERE DEPTNO=; Dbms_output. Put_Line (V_row. dname); END; Can be used in the cursor and our table drip ah;V_row

1. Simple VariablesDECLARE v_cnt number (10,0): = 0; BEGIN SELECT COUNT (1) into v_cnt from concept. decoction WHERE Decoctionid =-1; IF v_cnt = 0 Then insert INTO concept. Decoction (Decoctionid, Code, Name, Mnemoniccode, Spellcode, Wbcode, Clinicitemid, Isspecial, IsDeleted, RowVersion, Isne Edaccount) VALUES (-1, NULL, NULL, NULL, NULL, NULL,-1, 0, 0, sysdate, 0); END IF; END;2. Variables defined in the table's field typeCREATE TABLE DBO. TEST_TBL (ID number () not NULL PRIMARY KEY);d eclare

The number/frequency of SQL queries in ORACLE and the number of SQL queries in oracle In ORACLE Database Application optimization, the execution Frequency/frequency of an SQL statement is also frequently concerned, because the exe

Oracle Advanced SQL (4) -- SQL column and column conversion topic 2, oracle -- SQL [Previous topic] column-and-column conversion 1-Introduction to functions of aggregate and unaggregate Implementation case 1001: lufei1001 shanzhi1001 namei1001 qiaoba: 1001 lufei, shanzhi, na

replaced by this format. 4. Add the TNS_ADMIN environment variable to point to the created tnsnames. ora configuration file. So far, the configuration has been completed. You can use tools such as pl/SQL developer to connect to a remote oracle database. The database is the name of the added tns Service (WSR here) If you want to

Method 1: As we all know, to connect to Oracle using PL/SQL, you need to install the Oracle client software. Have you ever wondered whether to directly connect to Oracle without installing the Oracle client? In fact, I always wanted to do this, because this client is so

SQL turning is a tool in the Quest Central software produced by Quest Corporation. Quest is an integrated, graphical, Cross-platform database management solution that can manage Oracle, DB2, and SQL Server databases simultaneously. Introduction to SQL tuning for SQL Serve

It was freezing, and I stayed at home and read "Mastering Oracle SQL" 2nd. I found that Oracle is still very powerful, and there are two hundred optical functions. It is difficult to simulate the Object-Oriented Query languages, in particular, Windows functions for OLAP in sql2003.Fortunately, hibernate3.0 also supports SQL