what are the main points that these examples are considered cursors? and why are they called explicit and implicit cursor.
explicit
for x in (select * from emp) loop
dbms_output.put_line('emp no: '||x.empno);
end loop;
implicit
select empno
into vEmpno
from empno
where empname = 'SCOTT';
for all we know that these are not clearly defined on the declaration area as cursor.
What is the difference between implicit cursor and explicit cursor in PL/SqL?
And what is ref cursor ?
difference between between these two constructs. Finally when i read the asktom.oracle.com , I was totally confused. The reason is thatTom says...we can retrieve more than one row in implicit cursor. If that would be case, what's the difference between these two cursors?? when to use?? My understanding was implicit cursors" ---> single-row queryExplicit cursors ---> multi-row query Experts
View 10 Replies View RelatedI want to return ref cursor based on explicit cursors
create table jumbo(id number, name varchar2(20));
insert into jumbo values(1,'jumbo');
create table mumbo(id number, name varchar2(20));
insert into mumbo values(1,'mumbo');
commit;
[Code].....
The above procedure has compilation errors when I am trying to open ref cursor
LINE/COL ERROR
-------- --------------------------------------------------------
20/24 PL/SQL: SQL Statement ignored
20/38 PL/SQL: ORA-00942: table or view does not exist
32/24 PL/SQL: SQL Statement ignored
32/38 PL/SQL: ORA-00942: table or view does not exist
SQL>
I need to open an explicit cursor for making a total: after I have to use the same information of that explicit cursor for dividing a column of the cursor by that total. It is not enough to open close, reopen and reclose because I just obtain one register at the same time and it is the same register two times consecutively.
I don't want to use auxiliary structures cause there are 18000 columns for 10200 rows.
FOR i IN 300..300 --18000
LOOP
y:=ymax-ysize*(i+0.5);
[Code]......
I am writing this procedure with a explicit cursors defined in it. However when i compile the procedure i get this error: Error(39,1): PL/SQL: SQL Statement ignored Error(39,1):PLS-00394: wrong number of values in the INTO list of a FETCH statement .
create or replace PROCEDURE PRO_ICMISd_customer_no BB_PM.customer_no%type;d_pr_code_bbl BB_PM.pr_code_bbl%type;d_pr_code_pmm BB_PM.pr_code_pmm%type;d_subdept_desc PM.subdept_desc%type;d_class_desc PM.class_desc%type;d_cat_desc PM.cat_desc%type;d_subcat_desc PM.subcat_desc%type;d_brand_name PM.brand_name%type;d_product_desc PM.product_desc%type;d_unit_price_bbl PM.unit_price%type; e_customer_no BB_PM.customer_no%type;e_pr_code_bbl BB_PM.pr_code_bbl%type;e_pr_code_pmm BB_PM.pr_code_pmm%type;e_subdept_desc PM.subdept_desc%type;e_class_desc PM.class_desc%type;e_cat_desc PM.cat_desc%type;e_subcat_desc PM.subcat_desc%type;e_brand_name PM.brand_name%type;e_product_desc
[code]....
I've tried to use implicit cursor in my pl/sql program and i get an error as following:
DECLARE
*
ERROR at line 1:
ORA-01422: exact fetch returns more than requested number of rows
ORA-06512: at line 17
Then,I tried to include an exception for it and the error is 'solved'.
DECLARE
d_call_id course.call_id%TYPE;
d_course_name course.course_name%TYPE;
d_term_desc term.term_desc%TYPE ;
d_f_first faculty.f_first%TYPE;
d_f_last faculty.f_last%TYPE;
d_day course_section.c_sec_day%TYPE;
d_time course_section.c_sec_time%TYPE;
d_bldg_code location.bldg_code%TYPE;
d_room location.room%TYPE;
[code]....
By actually the program are suppose to return the records instead or returning the error. I've included the table that i'm trying to retrieve the records from as well.
Oracle Version: 11.2.0.2.0. I have two explicit cursors and I would like to choose at run time which one to run. Here is a simplified code snippet of what I am doing today:
DECLARE
CURSOR Cursor_A IS
SELECT * FROM EMP_A;
CURSOR Cursor_B IS
SELECT * FROM EMP_B;
RUNA CHAR(1) := 'Y';
[code]....
I want to avoid maintaining the same long list of transformations. I also want to avoid, if possible, an explicit FETCH INTO, because there are hundreds of fields in both tables. I'm looking for something like this (and I know this doesnt work):
DECLARE
CURSOR Cursor_A IS
SELECT * FROM EMP_A;
CURSOR Cursor_B IS
SELECT * FROM EMP_B;
RUNA CHAR(1) := 'Y';
CursorToRun IS REF CURSOR;
[code]....
1) SQL Statements are not using IMPLICIT CURSORS.
2) Only the SQL statements of the PLSQL program create implicit cursors.
We all know that commit will do the following.
1. Save the Txn Permanently to the database.
2. Release the table locks and
3. Erase the save points.
TABLE NAME:
==========
create table TEST_PREC (NO NUMBER(4,2));
DECLARE
BEGIN
INSERT INTO TEST_PREC VALUES (12.34);
DBMS_OUTPUT.PUT_LINE('the no of records before commit '||SQL%ROWCOUNT);
commit; /* What's happening inside commit */
[code]....
why the SQL%ROWCOUNT is set to zero after commit.
Does the commit, close the implicit cursor?
Need some Clarification on the below query:
Can we specify explicit name for the index of the IOT.
I have written a purge package that would delete records older than 10 years. Since the data is huge, the purging was taking 14 hours plus. To improve performance, I disabled constraints , deleted records and then reanabled them. This was quite quick but the only problem is rollback. Say for some reason if enabling constraints fails there is no way to rollback as enabling and disabling constraints does an implicit rollback.
View 1 Replies View RelatedI'm working on a Java-based web application and we have unit tests that we use to test all our all code that interacts with the database or code that interacts with our DB code. The Spring framework allows us to perform some DML within a transaction before each test and then rollback the changes. For the most part, this works, however when I run the full suite of unit tests, it will randomly commit data to the database causing the rest of the tests to fail.
will Oracle's auditing let me see where this odd-ball commit is occurring? Is there another way for me to see when data is being committed?
This does not appear to be happening on any of the systems we've deployed, however this is a bit unsettling and would like to know why this is occurring so that we can prevent it from happening in production.
I have two Schemas
DMS_NS_STG_1,DMS_NS_STG_2
Both are having same tables but with diffrent data. I want to write a generic code piece for a table to get that diffrences out, it can be for multiple tables. There will be a DB link between two DB.
1. What's the differences between CAT and TAB?
2. Why doesn't TAB exist in dict?
3. What the appropriate situation for CAT and TAB?
sys@ORCL> desc cat
Name Null? Type
----------------------------------------------------- -------- ------------------------------------
TABLE_NAME NOT NULL VARCHAR2(30)
TABLE_TYPE VARCHAR2(11)
sys@ORCL> desc tab
Name Null? Type
----------------------------------------------------- -------- ------------------------------------
TNAME NOT NULL VARCHAR2(30)
TABTYPE VARCHAR2(7)
CLUSTERID NUMBER
sys@ORCL> select * from dict where table_name='CAT';
TABLE_NAME COMMENTS
---------- -----------------------------------
CAT Synonym for USER_CATALOG
sys@ORCL> select * from dict where table_name='USER_CATALOG';
TABLE_NAME COMMENTS
-------------------- -----------------------------------------------------------------
USER_CATALOG Tables, Views, Synonyms and Sequences owned by the user
we get daily a full dump from our customer. We have to build the differences of tables (deltas) and load them in separate tables.
There some questions, requiremenst and restrictions:
1) Is it possible the merge the dumps ?
2) How to build the differences as the easiest ?
3) The whole process (import, merge, extract) should be run in batch.
4) We have only a solid knowledge and liitle time for doing.
I am planing to write the web-application which use Oracle DB 11g.I would like to understand what are the differences (specially, performance issues, steps of execution, optimizer possibilities) between calling SQL statements and PL/SQL procedures/functions. Which approach is more appropriate, and why?
Examples:
a) WebApp->Call("select * from employees where department_id = ?", 10) ;
b) WebApp->Call("? := mypackage.get_emp(?)", refCursor, 10);
create package mypackage is
function get_emp(dep_id in number) return sys_refcursor is
begin
open cur for select * from employees where department_id = dep_id;
end;
end;==========================================
Requirements: High-concurrency, 100+ db sessions, DB will not be used for business-logic.
In my Project, there are many queries have join conditions between Number and Vrahchar2. Will it give any wrong results or Invalid Number exception even the varchar2 column always contains the number data?
Example:
Select * from Table_t1 t1, table_t2 t2
where t1.num_col = t2.var_col
-- Here var_col always hold only numaric data.
we have an issue on a server, where if we insert a value containing foreign characters from SQL+ we see it screwed up from SQLdev, whereas if we do the same insert from SQLdev it's then screwed up in SQL+.
All operations are performed on the DB server itself, SQLdev connection type is TNS and the entry being used is the same as the one used by SQL+.We checked v$nls_parameters and the values contained there are the same from both SQL+ and SQLdev.
We have recently upgraded application (from Oracle Applications 11.5.9 to 12.1.3) and database (from 9.2.0.5.0 to 11.2.0.3.0).Since we are confronting to performances issues, i try to analyse some queries which Explains plans seems strange (in my opinion).Studying one of them i discover the next case (which according to my logic, i can't explain): --
Just bind variable --select *from MTL_MATERIAL_TRANSACTIONS mmtwhere 1 = 1and mmt.INVENTORY_ITEM_ID = :p1and mmt.ORGANIZATION_ID = :p2and mmt.TRANSACTION_REFERENCE = :p3--and mmt.SUBINVENTORY_CODE = :p4 PlanSELECT STATEMENT ALL_ROWS Cost: 5 Bytes: 361 Cardinality: 1 2 TABLE ACCESS BY INDEX ROWID TABLE INV.MTL_MATERIAL_TRANSACTIONS Cost: 5 Bytes: 361 Cardinality: 1 1 INDEX RANGE SCAN INDEX XXSPE.XXSPE_MTL_MATERIAL_TRANSAC_N99 Cost: 3 Cardinality: 2-- Nvl on bind variable --select *from MTL_MATERIAL_TRANSACTIONS mmtwhere 1 = 1and mmt.INVENTORY_ITEM_ID = :p1and
[code]...
We have the following scenario:
1) We get a daily Oracle 11 Dump
2) We only want to import the current changes in a MySQL database .
For this we need:
a) Is there a tool, script or best practices to get only the differences (delta) ?
b) How to import an Oracle dump or only teh differences into a MySQL database ?
differences of enabling thread as public or private?
lets assume that i have two threads (1, 2) for two instances (1, 2) and each of thread consists of 2 redolog groups - minimum configuration.in case i need add third node i need third thread.
what will be difference if i set this thread as public instead private?
I have an existing view that stores some data. I was asked to create a table based on the columns present in the view. I only copied the table structure from the view.
Now I would need to create a stored procedure that executes the query and stores the data in the table with a snap id and date of snap column. The reason this needs to be done is to show differences over time for historical and trending.
i write a select statement in proc that contains 44 columns.
when i precompile it. it is showing the error: implicit conversion of string literal to "char *" is deprecated.when i compile the same select with 40 columns it is not showing any error.
but for more than 40 columns (41-44) it is showing the above error.
We are trying to use the methods/constructors in the object types and find it more similar to the procedures and functions in the packages. I am wondering how they are different from stored procs and functions and what are the advantages?
View 2 Replies View RelatedHow oracle deals with the setting of init.ora parameter compatible.
e.g. we have
DB Version=10.2.0.4
compatible=10.2.0
what is the possible leak for us ? Is there any description about the features changed in 10.2 up to 10.2.0.4 in all steps - so that we can check out which functions we do not have.
I am trying to compile a .pc file with the make file which I created. But when I try to give make command I am getting following error
>make testfile
cc -o testfile testfile.c
"testfile.c", line 117: warning: no explicit type given
"testfile.c", line 119: warning: no explicit type given
"testfile.c", line 121: warning: no explicit type given
"testfile.c", line 122: warning: no explicit type given
"testfile.c", line 123: warning: no explicit type given
Undefined first referenced
symbol in file
sqlcxt testfile.o
ld: fatal: Symbol referencing errors. No output written to testfile
*** Error code 1
make: Fatal error: Command failed for target `testfile'
My oracle backup via Netbackup failing with error 6 (Netbackup) and i have checked the logs please find the RMAN log file as well.
Script /opt/rman_script/st72_oracle_full.sh
==== started on Tue May 28 15:27:46 SGT 2013 ====
RMAN: /OraBase/V10203/bin/rman
ORACLE_SID: ST72
ORACLE_USER: oracle
ORACLE_HOME: /OraBase/V10203
NB_ORA_FULL: 1
NB_ORA_INCR: 0
[code]....
I'm dealing with an ORA-1000 error in a Pro*C application where all the cursors are correctly closed (or so it seems to me).
Here is the code for a simple program which reproduces the problem:
Each cursor is opened in a PL/SQL package:
CREATE OR REPLACE PACKAGE emp_demo_pkg AS
TYPE emp_cur_type IS REF CURSOR;
PROCEDURE open_cur(curs IN OUT emp_cur_type, dept_num IN NUMBER);
END emp_demo_pkg;
[Code]....
While testing the initialization parameter open_cursors is set to 50.
It's my understanding that Oracle doesn't close the cursors until it needs the space for another cursor, which in my test case seems to happen when I enter a value of 50 or bigger for "number of loops". To see how oracle is reusing the cursors, while the test program is running I run SQL*Plus and query v$sesstat for the session that's running the test with the following sentence:
select name, value
from v$sesstat s, v$statname n
where s.statistic# = n.statistic#
and sid = 7
and name like '%cursor%';
Even before I enter a value for number of loops I can see that the session opened 4 cursors and closed 2 of them:
NAME VALUE
---------------------------------------------------------------- ----------
opened cursors cumulative 4
opened cursors current 2
Entering a value of 5 for number of loops yields
NAME VALUE
---------------------------------------------------------------- ----------
opened cursors cumulative 11 <----- 7+
opened cursors current 8 <----- 6+
With a value of 30
NAME VALUE
---------------------------------------------------------------- ----------
opened cursors cumulative 36 <----- 25+ (apparently, Oracle reused at least 5 cursors)
opened cursors current 33 <----- 25+
With a value of 47
NAME VALUE
---------------------------------------------------------------- ----------
opened cursors cumulative 53 <----- 17+
opened cursors current 50 <----- 17+
Now I reached the upper limit set by the initialization parameter open_cursors.
Entering a value of 48, I get the ORA-1000 error.
ORA-01000: maximum open cursors exceeded
ORA-06512: at "SCOTT.EMP_DEMO
Since I open and close the cursor in the same loop iteration, I expect to find in every iterarion 1 explicit cursor and a number of implicit cursors (the PL/SQL call along with the so-called recursive cursors), but I don't expect the sum of all of them to be greater than 50. If my understanding is correct Oracle should be reusing the 50 cursors previously marked as "closeable", not raising the ORA-1000 error.
Is it possible to:
-define a cursor with bind variables
-get a cursor record from these cursor
-and pass the bind variable in the OPEN clause
Did'nt succeed as shown in the example.
SET SERVEROUTPUT ON SIZE 900000;
DECLARE
--works fine
CURSOR c1 IS SELECT * FROM USER_TABLES WHERE rownum<3;
--doesn't work
--CURSOR c1 IS SELECT * FROM USER_TABLES WHERE rownum<:1;
crec c1%rowtype;
BEGIN
--works fine
OPEN c1;
--isn't possible ?
--OPEN c1 USING 3;
[Code]....