The use of oracle index
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----
index
inverse key index
t1 colour varchar2(20)
index
blue 1
blue 2
red 3
7788 AAAAAAAA
7900 AAAA
7901 AAAAA
7788 100
7900 010
7901 001
OLAP
PL/SQL--------Procedure Language SQL Procedural SQL Language
PL/SQL basic components "block"
block
Declare
Variable Type Cursor
operative
begin ... end ;
SQL statement
exception handling partial exception
An error is reported in the capture executor/and can be further processed
---Executor
begin
grant select on emp to scott;
end;
/
dql---select sal from emp where empno=7788;
dml---update emp set sal=123;
tcl---commit;
ddl---drop table emp;
dcl---grant select on emp to scott;
DQL----into
DDL DCL---Dynamic SQL
----
begin
dbms_output.put_line('hello word !!!!! ');
end;
/
-------------------------Declarations
variables
declare
Variable name Variable type [initial value];
Scott Salary Inquiry
select sal from emp where empno=7788;
1 declare
2 vsal number;
3 begin
4 select sal into vsal from emp where empno=7788;
5 dbms_output.put_line(vsal);
6* end;
ABC[4]
extend
Array PL/SQL Table
record
id number
---------Array-----------
declare
type a_varrary is varray(11) of number;
va a_varrary ;
begin
va := a_varrary();
va.extend(11);
select sal,deptno,mgr into va(1),va(2),va(3) from emp where ename='SCOTT' ;
dbms_output.put_line(va(1)||'--'||va(2)||'----'||va(3));
end;
/
------PL/SQL Table-------
declare
type a_table IS TABLE of varchar2(10) index by binary_integer;
va a_table ;
begin
va(2) := 'abc';
va(3) :='ddd';
end;
/
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