triggers in pl sql

(V_empnoinch Number, V_ename outvarchar2, v_sal out Number) 3 is 4 5 begin 6 7 SelectEname,sal intoV_ename,v_sal fromEmpwhereEmpno=V_empno; 8 9Dbms_output.put_line ('Employee name is:'||v_ename); Ten OneDbms_output.put_line ('Employee Salary is:'||v_sal); AException - whenNo_data_found Then -Dbms_output.put_line ('Employee ID is error!'); the whenOthers Then -Dbms_output.put_line ('Others Error!'); - End;running under the system:

triggers. if you want to query the same trigger in the table, then the app should use the After keyword, because the trigger can query the table, or change it again the original changes only apply after the table is back to the consistent state. The above trigger has been written in such a way that it executes before any DELETE, insert, or update operation on the table, but can take one or more actions on the trigger, such as before DELETE, This will

), product_name varchar2 (+), Supplier_name varchar2 (+), Unit_price number (7,2)); CREATE TABLEProduct(product_id number (5), product_name varchar2 (+), Supplier_name varchar2 (+), Unit_price number (7,2));2) Create a Price_history_trigger trigger and executeCREATE or REPLACETRIGGER Price_history_triggerBeforeUPDATE of Unit_priceOn productFor each ROWBegininsert into product_price_historyvalues (: Old.product_id,:old.product_name,:old.supplier_name,:old.unit_ Price); end;/3) Modify the product'

PL/SQL based triggers and packagesPackage/* Packages : Encapsulation of related stored procedures, functions, variables, cursors, and exceptions There are declarations and the composition of the subject Advantages:1. Modular; 2. Easier application design ; 3. Information Hiding ; 4. Better Performance*/-- Declaration of package : keyword: Package is endCreate o

Conn Scott/tiger;grant insert,update,delete on EMP to System;conn system/orcl1234;create or replace VIEW V_empas select em Pno,ename,job,hiredate,deptno from Scott.emp;IndexIn order to improve the speed of the query, when the user is not satisfied with the query speed and needs to adjust the performance of the database, it is preferred to establish an index.CREATE INDEX idx_ename on employee (ename, Sal DESC);Proper use of indexes can improve the speed of data retrieval and can create indexes on

The following describes how to debug a function. Other debugging operations are the same.1. Generally, there are two places to debug the program in pl/SQL Dev: 1). New-> test window: www.2cto.com2) Right-click the program to be debugged and choose test.2. debugging process 1). Enter the testing window through the debugging position, for example:Click position 1 (or press F9) to enter the debugger. Position

The following describes how to debug a function. Other debugging operations are the same. 　　1. debugging location In general, there are two places to debug the program in pl/SQL Dev: 1). New-> test window: 2) Right-click the program to be debugged and choose test. 　　2. debugging process 1) enter the test window through the debugging position, for example: Click position 1 (or press F9) to enter the debug

The When clause describes the triggering constraint condition. When condition is a logical expression, it must contain a correlation name, not a query statement, or a PL/SQL function. The trigger constraint specified by the When clause can only be used in before and after row triggers, not in instead of row triggers an

progressive in a non-trivial way (that is, the growth stride is not 1), you have to write some clever code, here's a simple example: using simple multiplication in a loop, the recursion takes only half the number of times: (Not quite) for inch 1 - LOOP calc_values (even_number*2); END LOOP; Looping Tags: you can give a loop name by label, format: All_emps>> forEmp_recinchemp_cur LOOP ...ENDLOOP;--tags can also be followed by end loop reserved words, which are optional Year_loop>> wh

. Result set object (using cursor) Sql:string sql = "{call Mypackage.queryemplist (?,?)}"; Call the stored procedure with the cursor Call.registeroutparameter (2, oracletypes.cursor); Cursor type Data dictionary Meta Data Database framework Triggers: Row-level triggers, statement-level triggers Instance: /*implement co

--Create a functionCreate or Replace function Add_sal (ssal number) return numberIsBegin if (Ssal >) Then return ssal + 51; elsif (Ssal >) Then return ssal + 111; Else return ssal + 222; End If;EndSelect Sal, Add_sal (SAL) from EMP;--TriggerCREATE TABLE Deptlog ( UName varchar2 (20), Action Varchar2 (20), DTime Date);--Create a trigger--for each row can trigger multiple entries, and how many times your language affects how many records will be triggeredCreate