oracle review

statementsDaclarestrSQL varchar2 (100);Beginstrsql:= ' CREATE table TTT (a mumber) ';Excute immediate (strSQL);EndCursorDeclareCursor "vernier keyword" c1 is a select empno, ename,job from EMP;BeginOpen C1;Fetch C1 into emp.empno,emp.ename,emp.job;While C1%found loopDbms_output.put_line ();Fetch C1 into emp.empno,emp.ename,emp.job;End Loop;Close C1;EndTriggerTable-level triggers are executed only once when several rows are inserted at a time, and row-level triggers are executed once by insertin

Oracle review, oracle After I got back, I recorded several sets of videos, but I didn't know how to record them when I started recording them. If I recorded a few sets, I had nothing to do. I could record each set for dozens of minutes, in the process, I also read this part of the Oracle database, and gained a lot. lea

A review of the IT Ninja Turtles oracle grouping method, Ninja Turtles oracle Oracle analysis functions are very powerful. We only need to master these methods. A more direct saying is that knowing the functions of these analysis functions can accomplish a lot of work. The following describes these functions and simple

IT Ninja Turtles oracle connect by usage review, Ninja Turtles oracle First use the emp table of scott.The emp table has one field: empno (employee ID) and mgr (Superior manager ID)Below are all the data in the table 1 select*fromemp start withempno=7698connectbymgr=priorempno; The execution result is as follows: The result is the data of empn

"Book Review: Oracle Query Optimization Rewrite" chapter fourth Blog Document structure diagram 650) this.width=650; "title=" wpse60b.tmp "border=" 0 "alt=" wpse60b.tmp "src=" http://s3.51cto.com/wyfs02/M00/6D/0B/ Wkiom1varbyhcepqaabjdaqoiyu258.jpg "" 291 "height=" 192 "/>I. 1 guideTechnical enthusiasts, after reading this article, you can master the following skills, you can also learn some other knowledge

IT Ninja Turtles-A Review of oracle grouping Methods Oracle analysis functions are very powerful. We only need to master these methods. A more direct saying is that knowing the functions of these analysis functions can accomplish a lot of work. The following describes these functions and simple applications. Here, I want to explain to the lag () and lead () funct

CREATE TABLE T_name (ID number,name varchar2 (Ten));d ROP Table T_name;select * FROM table_name where id = 2; INSERT INTO tabl E_name (C_01,C_02) VALUES (1, ' Terry '); update table_name Set name = ' Tyron ' WHERE id = 1;delete from table_name where id = 3;DECLAREV_01 number (5,2); beginv_01: = 100/6;dbms_output.put_line (v_01);--16.67end;/　　SELECT * from user_source where name = ' procedure_name ';--get code for created stored procedure select * from user_procedures;--query created stored proce

Today, when you log in to the Oracle database EM, there is a picture.I found a lot of information and found no solution. After some research, I found that maybe I changed my computer's name yesterday, which caused my em to not log in.WORKAROUND: Restore the previous computer name.Step: 1. Open Control Panel, system and safety system2. Locate the computer name, domain, and workgroup settings, and click Change Settings3. Under the Pop-up window (compute

), cascade, automatically update the child table countries the region_id of the original country in the region. CREATE OR REPLACE TRIGGERTr_reg_couafterUpdate ofregion_id onRegions forEach ROWBEGINDbms_output. Put_Line ('the old region_id value is'||: old.region_id||', the new region_id value is'||: new.region_id); UPDATECountriesSETregion_id=: new.region_idWHEREregion_id=: old.region_id;END; Example 5: Invoking a procedure in a trigger. CREATE OR REPLACE PROCEDUREadd_job_history (p_emp_id job_

Oracle.sql.BLOB. When you do not use LOB classes provided by the database JDBC driver, the program is run with an "abstract method call" error, because the Java.sql.Clob defined by JDBC and Java.sql.Blob interface, some of which are not actually implemented in the driver provided by the database manufacturer. 5, access means and file operation similar. For BLOB types, the Inputstream/outputstream class is applied, and this class does not encode conversions and accesses bytes-by-byte. The Oracle

This morning, I completed the task I proposed for myself yesterday. I finally finished reading PDF files online. At the same time, I solved new problems and added the hand-shaped cursor to control translation. The modification of batch video conversion was not done, mainly because I attended an introduction lecture on Oracle Spatial 11g in the afternoon. Oracle Spatial 11g lecture is a technical engineer

Label:This article is original article, reprint please indicate source: http://blog.csdn.net/msdnchina/article/details/42425491Hardware engineers move storage (new plus storage, do other things for storage), and before they do, Oracle DBA is ready to work:1.VG information hpux:vgdisplay,pvdisplay, Vgdisplay-v vg_data Aix is: Lsvg-o, lsvg,lsvg datavg,lsvg-l datavg, LSPV 2.OCR + VD information (if RAC) 3.datafile information (v$dbfile,v$datafile,d

main function of the Oracle analysis function: To take the first few, or the last few "sample" table content as follows: Name | seqno | Descriptiona | 1 | TestA | 2 | TestA | 3 | TestA | 4 | Testb | 1 | Testb | 2 | Testb | 3 | Testb | 4 | TESTC | 1 | TESTC | 2 | TESTC | 3 | TESTC | 4 | Test I want to have an SQL statement, the result of the search is a | 1 | TestA | 2 | Testb | 1 | Testb | 2 | TESTC | 1 | TESTC | 2 | Test implementation: Select Name,

, column_count out number)Cursor mycu is select jb_type from rep_synch group by jb_type;Jb_type _ varchar2 (50): = '';SQL _ varchar2 (2000): = 'select to_char (to_date (sj_time, ''yyyy-mm-dd hh24: MI: s''), ''mm '') month ';BeginFor Cu IN mycuLoopJb_type _: = Cu. jb_type;Column_count: = mycu % rowcount;SQL _: = SQL _ | ', count (case when jb_type = ''' | jb_type _ | ''' then ID end)' | jb_type _;End loop;SQL _: = SQL _ | ', count (ID) Total from rep_synch group by to_char (to_date (sj_time, ''yy

The permission system of the oracle database includes system permission and object permission. Database system privilege allows users to execute specific command sets. For example, the create table permission allows users to create tables, and the grant any privilege permission allows users to grant any system permissions. Database object privilege allows you to perform certain operations on each object. For example, the delete permission allows y

Oracle indexes refer to the data structure of ORACLE indexes in B tree structure and bitmap structure. The common indexes, reverse key indexes, and function indexes we usually use are tree structures and tree structures;The bitmap structure only has leaf nodes. B-tree INDEX operations have unique scans, range scans, and FAST FULL INDEX scans (INDEX FAST FULL SCAN ),Full index scan (index full scan); the acc

), Max (Sal), Min (sal) from EMP;6: Group queries--Query the average salary of each department (grouped by department)Select Floor (avg. sal), Deptno from EMP Group by DEPTNO;--Query the total salary and average wage of each department and the maximum wageSelect Floor avg (SAL) as average salary, sum (SAL) Total wages, Max (SAL), Deptno from EMP Group by DEPTNO;--Query Each department, the total wages of each job andSelect SUM (SAL) Total wages, deptno, job from EMP Group by Deptno,job--Check ou

Oracle 10g Oracle is designed for Grid computing, the G in 10g refers to the grid computing Oracle stores data in files, files that hold different information (data files, control files, log files) make up the physical structure of the database Logical structure: Schema, extent, data block, segment A collection of Schema database objects that, when created, gener

Well, I also Finon, because in the company's year-end goal of writing to learn Oracle, today began Oracle, to give you a new understanding of it! Not going to hit me! ~ Quack. Actually, to be honest, I don't want to write theory in this respect, but for the integrity of a series, I still have to bite the bullet to write it. I will try to use the colloquial language for those more blunt terminology, of cour

Oracle Database Performance Optimization general rule:One, reduce data access (reduce the number of drive room visits)Second, return less data (reduce network transmission or disk access)Third, reduce the number of interactions (reduce network transmission)Iv. reduced server overhead (reduced CPU and memory overhead)V. Utilization of additional resources (increased resources)=================== Specific Instructions =================One, reduce data a