I am running many procedures parallel through java thread code. I have used exception handling in my procedures in order to catch any error results. When i see java debugger log i can see few of the procedures throws an error ORA-00054: resource busy and acquire with NOWAIT specified or timeout expired. I am using few tables which are in common and used by other procedures as well. I dont know the reason why this issue is comming.
PROCEDURE "EXT_10024_ACTIVATE_OPTION"(IN_KPI_DEF_ID IN NUMBER DEFAULT 0) AS
IN_EVENT_ID NUMBER;
err_code VARCHAR(100);
err_msg VARCHAR(100);
IN_OBJECT_NAME VARCHAR2(100);
CURSOR KPI_DEF_CUR IS
Select KPI_DEF_ID,BUSINESS_CHECK_PERIOD_ID,BUS_CHK_PRD_ID_1,
CASE WHEN BUSINESS_CHECK_PERIOD_UNIT_ID=11 THEN 'MINUTE'
WHEN BUSINESS_CHECK_PERIOD_UNIT_ID=12 THEN 'HOUR'
WHEN BUSINESS_CHECK_PERIOD_UNIT_ID=13 THEN 'DAY'
WHEN BUSINESS_CHECK_PERIOD_UNIT_ID IS NULL THEN 'MINUTE'
END AS BUSINESS_CHECK_PERIOD_UNIT_ID,
CASE WHEN BUSINESS_CHK_PERIOD_VAL IS NULL THEN 0
ELSE BUSINESS_CHK_PERIOD_VAL END AS BUSINESS_CHK_PERIOD_VAL,
CASE WHEN BUS_CHK_PRD_UNIT_ID_1=11 THEN 'MINUTE'
WHEN BUS_CHK_PRD_UNIT_ID_1=12 THEN 'HOUR'
WHEN BUS_CHK_PRD_UNIT_ID_1=13 THEN 'DAY'
WHEN BUS_CHK_PRD_UNIT_ID_1 IS NULL THEN 'MINUTE'
END AS BUS_CHK_PRD_UNIT_ID_1,
CASE WHEN BUS_CHK_PRD_VAL_1 IS NULL THEN 0
ELSE BUS_CHK_PRD_VAL_1 END AS BUS_CHK_PRD_VAL_1,
EVENT_ID FROM RATOR_MONITORING_CONFIGURATION.KPI_DEFINITION where KPI_DEF_ID = IN_KPI_DEF_ID;
BEGIN
--delete the data from TEMP_SERVICE_OPTION and TEMP_SERVICE_OPTION_EXTRACTION
EXECUTE IMMEDIATE 'TRUNCATE TABLE TEMP_ACTIVATE_OPTION';
EXECUTE IMMEDIATE 'TRUNCATE TABLE TEMP_SERVICE_OPTION_EXTRACTION';
EXECUTE IMMEDIATE 'TRUNCATE TABLE TEMP_SERVICE_OPTION';
DELETE FROM CAPTURED_DATA_ERROR WHERE EVENT_TIMESTAMP < SYSDATE - 60 and EVENT_ID=10024;
-- removed, retrieve a new START_ID from source first, don't use the last id.
-- SELECT LAST_TASK_ID INTO LAST_SO_ID FROM CAPTURING where DB_TABLE='TEMP_SERVICE_OPTION';
--SELECT MIN(SO.ID) INTO LAST_SO_ID FROM SERVICE_OPTION#FONIC_RETAIL SO WHERE SO.ID >= to_char(SYSDATE -1, 'YYYYMMDDHH24MISS')||'0000';
Select EVENT_ID INTO IN_EVENT_ID FROM RATOR_MONITORING_CONFIGURATION.KPI_DEFINITION where KPI_DEF_ID = IN_KPI_DEF_ID;
FOR KPI_DEF_ROW IN KPI_DEF_CUR
LOOP
BEGIN
INSERT INTO TEMP_ACTIVATE_OPTION(ID,ICC,ASSIGNED_ANUMBER_ID,SERVICE_ID,PRODUCT_OPTION_ID,STATUS_ID,END_DATE,PRODUCT_TYPE_KEY)
Select DISTINCT(SO.ID),SIM.ICC,SIM.ASSIGNED_ANUMBER_ID,SO.SERVICE_ID,SO.PRODUCT_OPTION_ID,SO.STATUS_ID,SO.END_DATE,SIM.PRODUCT_TYPE_KEY FROM
SIMCARD#FONIC_RETAIL SIM
JOIN SERVICE_OPTION#FONIC_RETAIL SO ON SO.SERVICE_ID=SIM.ASSIGNED_TO_SERVICE_ID
where SO.STATUS_ID IN (20,40)
and SO.ID < to_char(SYSDATE - numtodsinterval ( KPI_DEF_ROW.BUSINESS_CHK_PERIOD_VAL,KPI_DEF_ROW.BUSINESS_CHECK_PERIOD_UNIT_ID ), 'YYYYMMDDHH24MISS')||'0000'
and SO.ID > to_char(SYSDATE - numtodsinterval ( KPI_DEF_ROW.BUS_CHK_PRD_VAL_1, KPI_DEF_ROW.BUS_CHK_PRD_UNIT_ID_1 ), 'YYYYMMDDHH24MISS')||'0000'
and NOT EXISTS(SELECT ID from TEMP_ACTIVATE_OPTION T WHERE T.ID = SO.ID );
EXCEPTION WHEN NO_DATA_FOUND THEN
DBMS_OUTPUT.PUT_LINE('NO_DATA_FOUND exception in EXT_10024_ACTIVATE_OPTION - KPI_DEF_ID:'||to_char(IN_KPI_DEF_ID));
RAISE;
END;
commit;
BEGIN
INSERT INTO TEMP_SERVICE_OPTION_EXTRACTION(ID,ICC,ASSIGNED_ANUMBER_ID,SERVICE_ID,PRODUCT_OPTION_ID,STATUS_ID,END_DATE,A_NUMBER,PRODUCT_TYPE_KEY)
Select DISTINCT(SO.ID),SO.ICC,SO.ASSIGNED_ANUMBER_ID,SO.SERVICE_ID,SO.PRODUCT_OPTION_ID,SO.STATUS_ID,SO.END_DATE,AN.A_NUMBER,SO.PRODUCT_TYPE_KEY FROM
TEMP_ACTIVATE_OPTION SO JOIN
PRODUCT_OPTION#FONIC_RETAIL PO ON SO.PRODUCT_OPTION_ID = PO.ID JOIN
PRODUCT_CONFIG#FONIC_RETAIL PC ON PO.OPTION_KEY=PC.DEFAULT_PRODUCT_OPTIONS
JOIN PRODUCT_TYPE#FONIC_RETAIL PT ON PC.ID = PT.PRODUCT_CONFIG_ID
JOIN TEMP_ACTIVATE_OPTION SO ON SO.PRODUCT_TYPE_KEY=PT.KEY
JOIN
A_NUMBER#FONIC_RETAIL AN ON SO.ASSIGNED_ANUMBER_ID = AN.ID
where SO.STATUS_ID IN (20,40)
and NOT EXISTS(SELECT ID from TEMP_SERVICE_OPTION_EXTRACTION T WHERE T.ID = SO.ID );
EXCEPTION WHEN NO_DATA_FOUND THEN
DBMS_OUTPUT.PUT_LINE('NO_DATA_FOUND exception in EXT_10024_ACTIVATE_OPTION - KPI_DEF_ID:'||to_char(IN_KPI_DEF_ID));
RAISE;
END;
commit;
BEGIN
--SELF_REGISTRATION ACTIVATE OPTION
INSERT INTO TEMP_SERVICE_OPTION(ID,SERVICE_ID,PRODUCT_OPTION_ID,STATUS_ID,EVENT_TIMESTAMP,END_DATE,EVENT_ID,SUBSCRIPTION_ID,ORDER_NUMBER,A_NUMBER)
Select DISTINCT(SO.ID),SO.SERVICE_ID,SO.PRODUCT_OPTION_ID,SO.STATUS_ID,to_date(substr(SO.ID, 1, 14), 'YYYYMMDDHH24MISS'),SO.END_DATE,
IN_EVENT_ID
,TSM.SUBSCRIPTION_ID,TSM.ORDER_NUMBER,SO.A_NUMBER
from TEMP_SERVICE_OPTION_EXTRACTION SO JOIN TMP_SOAP_MONITORING_IDS TSM
ON SO.A_NUMBER = TSM.MSISDN
where SO.STATUS_ID IN (20,40) and TSM.ORDER_TYPE='SELF_REGISTRATION' and
TSM.CREATE_DATE < SYSDATE - numtodsinterval ( KPI_DEF_ROW.BUSINESS_CHK_PERIOD_VAL,KPI_DEF_ROW.BUSINESS_CHECK_PERIOD_UNIT_ID )
and TSM.CREATE_DATE > SYSDATE - numtodsinterval ( KPI_DEF_ROW.BUS_CHK_PRD_VAL_1, KPI_DEF_ROW.BUS_CHK_PRD_UNIT_ID_1 )
and NOT EXISTS(SELECT ID from TEMP_SERVICE_OPTION T WHERE T.ID = SO.ID )
and TSM.WEB_SERVICE_NAME ='RatorWebShopService' and TSM.WEB_METHOD_NAME ='placeShopOrder';
EXCEPTION WHEN NO_DATA_FOUND THEN
DBMS_OUTPUT.PUT_LINE('NO_DATA_FOUND exception in EXT_10024_ACTIVATE_OPTION - KPI_DEF_ID:'||to_char(IN_KPI_DEF_ID));
RAISE;
END;
END LOOP;
commit;
--INSERT TEMP DATA INTO CAPTURED_DATA_01 TABLE
Insert into CAPTURED_DATA_01(SUBSCRIPTION_ID,ENV_ID,BRAND_ID,BP_ID,EVENT_ID,ORDER_ID,STATUS_DESCRIPTION,STATUS_CODE,EVENT_TIMESTAMP)
Select DISTINCT(DCR.SUBSCRIPTION_ID),BBE.ENV_ID,TSM.BRAND_ID,BBE.BP_ID,DCR.EVENT_ID,
DCR.ORDER_NUMBER,
CASE WHEN DCR.STATUS_ID=20 THEN 'OK'
WHEN DCR.STATUS_ID=40 THEN 'ERROR'
END,DCR.STATUS_ID,
DCR.EVENT_TIMESTAMP from TEMP_SERVICE_OPTION DCR JOIN TMP_SOAP_MONITORING_IDS TSM ON TSM.SUBSCRIPTION_ID=DCR.SUBSCRIPTION_ID
JOIN
RATOR_MONITORING_CONFIGURATION.ENV_BRAND_BP_EVENT BBE ON BBE.EVENT_ID = DCR.EVENT_ID JOIN
RATOR_MONITORING_CONFIGURATION.ENVIRONMENT ENV on BBE.ENV_ID=ENV.ENV_ID
JOIN RATOR_MONITORING_CONFIGURATION.BRAND BR ON BBE.BRAND_ID = BR.BRAND_ID
JOIN RATOR_MONITORING_CONFIGURATION.BUSINESS_PROCESS BP ON BBE.BP_ID = BP.BP_ID
AND NOT EXISTS(SELECT CD.SUBSCRIPTION_ID FROM CAPTURED_DATA_01 CD WHERE CD.EVENT_ID = DCR.EVENT_ID AND CD.SUBSCRIPTION_ID = DCR.SUBSCRIPTION_ID);
EXCEPTION WHEN OTHERS THEN
err_code := SQLCODE;
err_msg := SUBSTR(SQLERRM, 1, 200);
DBMS_OUTPUT.PUT_LINE('OTHERS exception in EXT_10072_REQ_SENT_SPAIN - KPI_DEF_ID:'||to_char(IN_KPI_DEF_ID) || err_code || '----' || err_msg || 'OBJECT_NAME->');
RAISE;
COMMIT;
END EXT_10024_ACTIVATE_OPTION;
The only thing in your code that can cause this is the TRUNCATE.
TRUNCATE is not DML. It's a DDL operation. It acquires a full table lock. Because you are doing some DML in other sessions (inserting particular rows), the session performing TRUNCATE cannot acquire the table lock. Somewhere internally NOWAIT is specified, so the exception is raised.
I believe you should reconsider using TRUNCATE here. It is DDL, it performs commit so it's not transactional. Obviously, it is not safe to use it in multi user environment.
You could use TEMPORARY TABLES. All the data you store in them only exists in your current session. This way you don't need to use TRUNCATE.
DDL will look something like this.
CRATE GLOBAL TEMPORARY TABLE TEMP_ACTIVATE_OPTION(
ID NUMBER,
... -- your columns
)
ON COMMIT DELETE ROWS;
TRUNCATE TABLE is a DDL command, and if unable to lock the table to perform the truncate, Oracle will raise ORA-00054. So if one session is using the table, another session cannot truncate it.
Related
I am trying to write a code block where record insert if record already exist then update
table. i am trying If (sql%rowcount = 0) then but it's not working in cursor and more one records.
What I tried so far as the code block is
declare
remp_id varchar2(60);
remp_name varchar2(100);
rdesig varchar2(100);
rdept_no number;
rdesig_no number;
rdept_name varchar2(60);
cursor alfa is
select emp_code, emp_name, desig, dept_name, dept_no, desig_no
from emp
where emp_code between :first_code and :second_code;
begin
open alfa;
loop
fetch alfa
into remp_id, remp_name, rdesig, rdept_name, rdept_no, rdesig_no;
exit when alfa%notfound;
update att_reg_mo
set emp_code = remp_id,
emp_name = remp_name,
desig = rdesig,
dept_name = rdept_name,
dept_no = rdept_no,
desig_no = rdesig_no,
att_date = :att_date,
emp_att = :emp_att,
att_type = 'MA',
reg_date = :reg_date
where emp_code between :first_code and :second_code
and reg_date = :reg_date
and att_date = :att_date;
commit;
if (sql%rowcount = 0) then
insert into att_reg_mo
(emp_code,
emp_name,
desig,
dept_name,
att_date,
emp_att,
att_type,
reg_date,
dept_no,
desig_no)
values
(remp_id,
remp_name,
rdesig,
rdept_name,
:att_date,
:emp_att,
'MA',
:reg_date,
rdept_no,
rdesig_no);
end if;
commit;
end loop;
close alfa;
end;
when i am fire the trigger then record is insert but where need to update record it's update with null values
Or you could use something like that:
DECLARE
cursor test is
select 1 as v from dual
union
select 2 as v from dual;
n_var NUMBER;
BEGIN
for rec in test loop
BEGIN
select 1 into n_var from dual where rec.v=2;
DBMS_OUTPUT.PUT_LINE('Please Update Any Table');
EXCEPTION
WHEN no_data_found THEN
DBMS_OUTPUT.PUT_LINE('Please Insert Any Table');
END;
end loop;
EXCEPTION
WHEN OTHERS THEN
DBMS_OUTPUT.PUT_LINE ('Unexpected error');
END;
SQL%attribute always refers to the most recently run SELECT or DML statement. It refreshes as to start from zero after any of transaction statement such as COMMIT, ROLLBACK or SAVEPOINT is issued, for a session in which AUTOCOMMIT is presumed to be OFF by default. Therefore, you always get zero from SQL%ROWCOUNT which is just before the INSERT statement, and keeping inserting to the concerned table during every run of code block.
So, remove the f i r s t COMMIT, removing also keeps the atomicity of the whole transaction, from your code block.
Demo
I need to have an update and insert wrapped into a transaction that will be called from an external web application. I'm trying to get back a basic success/failure status when it is called along with an error message if it failed.
What I would like to do is something like the following, but it gives me the following errors:
INTO clause is expected in this SELECT statement
"SQLCODE": invalid identifier
DECLARE STATUS VARCHAR2(128);
MESSAGE VARCHAR2(128);
BEGIN
UPDATE MYTABLE
SET COL1 = 400
WHERE USERNAME = 'bigtunacan' AND pk = 12345;
INSERT INTO MYTABLE (username, col1, col2)
VALUES('bigtunacan', 400, 'foo');
SELECT 'TRUE' AS STATUS, '' AS MSG FROM MYTABLE WHERE ROWNUM = 1;
COMMIT;
EXCEPTION
WHEN OTHERS THEN
ROLLBACK;
SELECT 'FALSE' AS STATUS, SQLCODE || SQLERRM AS MSG FROM MYTABLE WHERE ROWNUM = 1;
END;
Any Select statement inside a PL/SQL code needs an INTO clause, except the ones called from or within a cursor. In your case, You do not need to invoke any Select statement, but just assign static string values ('TRUE','FALSE') or pseudocolumns independent from SQL such as sqlcode or sqlerrm to your already defined variables.
So, consider using :
DECLARE
STATUS VARCHAR2(128) := 'TRUE';
MESSAGE VARCHAR2(128);
BEGIN
UPDATE MYTABLE
SET COL1 = 400
WHERE USERNAME = 'bigtunacan' AND pk = 12345;
INSERT INTO MYTABLE (username, col1, col2)
VALUES('bigtunacan', 400, 'foo');
-- SELECT 'TRUE' AS STATUS, '' AS MSG FROM MYTABLE WHERE ROWNUM = 1;
-- completely remove this above row, STATUS is already initialized as TRUE
COMMIT;
EXCEPTION
WHEN OTHERS THEN
ROLLBACK;
STATUS := 'FALSE';
RAISE_APPLICATION_ERROR(-20333,'Caution : An error was encountered -
'||SQLCODE||' -ERROR- '||SQLERRM);
END;
A Commit/Rollback should not be ideally included inside a called procedure. From Tom Kyte's own words:
I wish PLSQL didn't support commit/rollback. I firmly believe transaction control MUST be done at the topmost, invoker level.
You should consider converting your anonymous block into a procedure and define the transaction control in the invoker's code.
CREATE OR REPLACE procedure yourprocedure
( p_status OUT VARCHAR2,
p_message OUT VARCHAR2
) AS
BEGIN
UPDATE mytable
SET
col1 = 400
WHERE username = 'bigtunacan' AND pk = 12345;
INSERT INTO MYTABLE (username, col1, col2)
VALUES('bigtunacan', 400, 'foo');
p_status := 'TRUE' ;
p_message := NULL;
EXCEPTION
WHEN OTHERS THEN
p_status := 'FALSE' ;
p_message := SQLERRM ;
END;
/
Invocation ( May be another block, procedure or application layer )
DECLARE
l_status VARCHAR2(20);
l_message VARCHAR2(400);
BEGIN
yourprocedure(l_status,l_message);
IF
l_status = 'TRUE'
THEN
COMMIT;
ELSE
ROLLBACK;
END IF;
END;
/
Only exception is if it's defined as an Autonomous procedure (mostly used for logging purposes) where you are supposed to commit inside the procedure.
I am trying to write a deadlock proof stored procedure. It is based on the following concept.
I have been trying to write a stored procedure which is based on the following concept. The procedure will try to drop a constraint on a table and if in case it detects a deadlock situation, it wait for some time before trying again. The important thing is it should only retry in case of a Deadlock or a NOWAIT error, all other errors are to be handled via exceptions.
Procedure test
is
BEGIN
<<label>>
DROP constraint on a table
if (deadlock(ORA-00060)/Nowait Error (ORA-0054)) detected
then
sleep for 60 seconds
Goto label
exception
when others.
It would be great if any of the experts please help me with this. A similar example would be highly helpful. Thank you for your help.
While some people harbour an irrational aversion to goto it remains true that usually we can implement the same logic without using the construct. That is true here: a simple while loop is all that is necessary:
create or replace procedure drop_constraint_for_sure
( p_table_name in varchar2
, p_constraint_name in varchar2
)
is
x_deadlock exception;
pragma exception_init(x_deadlock, -60);
x_nowait exception;
pragma exception_init(x_nowait, -54);
begin
loop
begin
execute immediate 'alter table '|| p_table_name
|| ' drop constraint ' || p_constraint_name
|| ' cascade' ;
exit;
exception
when x_deadlock then null;
when x_nowait then null;
end;
dbms_lock.sleep(60);
end loop;
end;
/
Note that the sleep function requires the execute privilege on SYS.DBMS_LOCK. This is not granted by default, so if you don't have it you'll need to ask your friendly DBA to grant it.
Also note that this implementation doesn't have any form of abort. So it will loop eternally, until the constraint is dropped or some other exception occurs. In real life you should include a loop count with an additional exit test on a threshold for the count. Although in real life I probably wouldn't want a stored procedure like this anyway: I prefer knowing as soon as possible when someone is using a table I'm trying to alter.
Hope below snippet gives you can an idea to achieve your requirement.
CREATE OR REPLACE
PROCEDURE DRP_CONST_DEALDOCK
AS
DEADLOCK_EX EXCEPTION;
NO_WAIT_EX EXCEPTION;
PRAGMA EXCEPTION_INIT(DEADLOCK_EX,-60);
PRAGMA EXCEPTION_INIT(NO_WAIT_EX, -54);
lv_cnt PLS_INTEGER;
BEGIN
BEGIN
EXECUTE IMMEDIATE 'ALTER TABLE STACK_OF_TEST DROP CONSTRAINT SYS_C00375020';
EXCEPTION
WHEN DEADLOCK_EX THEN
dbms_output.put_line('nowait exception');
DBMS_LOCK.SLEEP(10);
SELECT COUNT(1)
INTO lv_cnt
FROM v$locked_object
WHERE object_id IN
(SELECT OBJECT_ID FROM DBA_OBJECTS WHERE OBJECT_NAME = 'STACK_OF_TEST'
);
WHILE lv_cnt > 0
LOOP
dbms_lock.sleep(10);
SELECT COUNT(1)
INTO lv_cnt
FROM v$locked_object
WHERE object_id IN
(SELECT OBJECT_ID FROM DBA_OBJECTS WHERE OBJECT_NAME = 'STACK_OF_TEST'
);
END LOOP;
WHEN NO_WAIT_EX THEN
dbms_output.put_line('nowait exception');
DBMS_LOCK.SLEEP(10);
SELECT COUNT(1)
INTO lv_cnt
FROM v$locked_object
WHERE object_id IN
(SELECT OBJECT_ID FROM DBA_OBJECTS WHERE OBJECT_NAME = 'STACK_OF_TEST'
);
WHILE lv_cnt > 0
LOOP
dbms_lock.sleep(10);
SELECT COUNT(1)
INTO lv_cnt
FROM v$locked_object
WHERE object_id IN
(SELECT OBJECT_ID FROM DBA_OBJECTS WHERE OBJECT_NAME = 'STACK_OF_TEST'
);
END LOOP;
WHEN OTHERS THEN
dbms_output.put_line(SQLCODE||'-->'||SQLERRM);
END;
END;
I need to drop an Oracle table only if it 1) exists AND 2) Is NOT Empty
I wrote this code but if the table does not exist the code does not work:
DECLARE
rec_cnt1 NUMBER :=0;
rec_cnt2 NUMBER :=0;
BEGIN
SELECT COUNT(*) INTO rec_cnt1 FROM ALL_TABLES WHERE TABLE_NAME = 'MyTable';
SELECT num_rows INTO rec_cnt2 FROM USER_TABLES WHERE TABLE_NAME = 'MyTable';
IF rec_cnt1 = 1 THEN
BEGIN
IF rec_cnt2 < 1 THEN
EXECUTE IMMEDIATE 'DROP TABLE MyTable cascade constraints';
END IF;
END;
END IF;
END;
/
What am I doing wrong? Please help.
Many thanks in advance
If you want to drop a table if it exists and empty(as the title of the question states) you could do this as follows:
create or replace procedure DropTableIfEmpty(p_tab_name varchar2)
is
l_tab_not_exists exception;
pragma exception_init(l_tab_not_exists, -942);
l_is_empty number;
l_query varchar2(1000);
l_table_name varchar2(32);
begin
l_table_name := dbms_assert.simple_sql_name(p_tab_name);
l_query := 'select count(*)
from ' || l_table_name ||
' where rownum = 1';
execute immediate l_query
into l_is_empty;
if l_is_empty = 0
then
execute immediate 'drop table ' || l_table_name;
dbms_output.put_line('Table "'|| p_tab_name ||'" has been dropped');
else
dbms_output.put_line('Table "'|| p_tab_name ||'" exists and is not empty');
end if;
exception
when l_tab_not_exists
then dbms_output.put_line('Table "'|| p_tab_name ||'" does not exist');
end;
When you are trying to drop a table, or query a table, which does not exist, Oracle will raise ORA-00942 exception and execution of a pl/sql block halts. We use pragma exception_init statement to associate ORA-00942 exception with our locally defined exception l_tab_not_exists in order to handle it appropriately.
Test case:
SQL> exec droptableifempty('tb_test'); -- tb_test table does not exists
Table "tb_test" does not exist
SQL> create table tb_test(
2 col number
3 );
table TB_TEST created.
SQL> exec droptableifempty('tb_test');
Table "tb_test" has been dropped
As a side note. Before querying num_rows column of [dba][all][user]_tables in order to determine number of rows a table has, you need to gather table statistic by executing dbms_stats.gather_table_stats(user, '<<table_name>>');, otherwise you wont get the actual number of rows.
In PL/SQL it is 'normal' to catch the exception.
If it is the correct exception then continue with the next part of your code.
DECLARE
rec_cnt1 NUMBER :=0;
rec_cnt2 NUMBER :=0;
BEGIN
SELECT COUNT(*) INTO rec_cnt1 FROM ALL_TABLES WHERE TABLE_NAME = 'MyTable';
SELECT num_rows INTO rec_cnt2 FROM USER_TABLES WHERE TABLE_NAME = 'MyTable';
IF rec_cnt1 = 1 THEN
BEGIN
IF rec_cnt2 < 1 THEN
EXECUTE IMMEDIATE 'DROP TABLE MyTable cascade constraints';
END IF;
END;
END IF;
EXCEPTION
DBMS_OUTPUT.PUT_LINE('OH DEAR AN EXCEPTION WAS THROWN DUE TO' || SQLERRM);
DBMS_OUTPUT.PUT_LINE('THE ORACLE CODE IS ' || SQLCODE);
-- if it is the oracle code for no such table, or no data selected
-- everything is fine.
END;
Of course it won't work if the table doesn't exist. Your second select would get a "No data found" exception, and you're not doing any exception handling. At least you should move the second select inside the first IF block. Best to add exception handling.
here is an easy way to solve this problem:
BEGIN
EXECUTE IMMEDIATE 'DROP TABLE [sssss]';
EXCEPTION WHEN OTHERS THEN NULL;
END;
Trying to check is table exist before create in Oracle. Search for most of the post from Stackoverflow and others too. Find some query but it didn't work for me.
IF((SELECT count(*) FROM dba_tables where table_name = 'EMPLOYEE') <= 0)
THEN
create table EMPLOYEE
(
ID NUMBER(3),
NAME VARCHAR2(30) NOT NULL
)
END IF;
Which gives me error
Error: ORA-00900: invalid SQL statement
SQLState: 42000
ErrorCode: 900
Position: 1
I search for the syntax for IF condition, I think which is also write.
Please suggest me....
As Rene also commented, it's quite uncommon to check first and then create the table.
If you want to have a running code according to your method, this will be:
declare
nCount NUMBER;
v_sql LONG;
begin
SELECT count(*) into nCount FROM dba_tables where table_name = 'EMPLOYEE';
IF(nCount <= 0)
THEN
v_sql:='
create table EMPLOYEE
(
ID NUMBER(3),
NAME VARCHAR2(30) NOT NULL
)';
execute immediate v_sql;
END IF;
end;
But I'd rather go catch on the Exception, saves you some unnecessary lines of code:
declare
v_sql LONG;
begin
v_sql:='create table EMPLOYEE
(
ID NUMBER(3),
NAME VARCHAR2(30) NOT NULL
)';
execute immediate v_sql;
EXCEPTION
WHEN OTHERS THEN
IF SQLCODE = -955 THEN
NULL; -- suppresses ORA-00955 exception
ELSE
RAISE;
END IF;
END;
/
I know this topic is a bit old, but I think I did something that may be useful for someone, so I'm posting it.
I compiled suggestions from this thread's answers into a procedure:
CREATE OR REPLACE PROCEDURE create_table_if_doesnt_exist(
p_table_name VARCHAR2,
create_table_query VARCHAR2
) AUTHID CURRENT_USER IS
n NUMBER;
BEGIN
SELECT COUNT(*) INTO n FROM user_tables WHERE table_name = UPPER(p_table_name);
IF (n = 0) THEN
EXECUTE IMMEDIATE create_table_query;
END IF;
END;
You can then use it in a following way:
call create_table_if_doesnt_exist('my_table', 'CREATE TABLE my_table (
id NUMBER(19) NOT NULL PRIMARY KEY,
text VARCHAR2(4000),
modified_time TIMESTAMP
)'
);
I know that it's kinda redundant to pass table name twice, but I think that's the easiest here.
Hope somebody finds above useful :-).
Please try:
SET SERVEROUTPUT ON
DECLARE
v_emp int:=0;
BEGIN
SELECT count(*) into v_emp FROM dba_tables where table_name = 'EMPLOYEE';
if v_emp<=0 then
EXECUTE IMMEDIATE 'create table EMPLOYEE ( ID NUMBER(3), NAME VARCHAR2(30) NOT NULL)';
end if;
END;
declare n number(10);
begin
select count(*) into n from tab where tname='TEST';
if (n = 0) then
execute immediate
'create table TEST ( ID NUMBER(3), NAME VARCHAR2 (30) NOT NULL)';
end if;
end;
My solution is just compilation of best ideas in thread, with a little improvement.
I use both dedicated procedure (#Tomasz Borowiec) to facilitate reuse, and exception handling (#Tobias Twardon) to reduce code and to get rid of redundant table name in procedure.
DECLARE
PROCEDURE create_table_if_doesnt_exist(
p_create_table_query VARCHAR2
) IS
BEGIN
EXECUTE IMMEDIATE p_create_table_query;
EXCEPTION
WHEN OTHERS THEN
-- suppresses "name is already being used" exception
IF SQLCODE = -955 THEN
NULL;
END IF;
END;
BEGIN
create_table_if_doesnt_exist('
CREATE TABLE "MY_TABLE" (
"ID" NUMBER(19) NOT NULL PRIMARY KEY,
"TEXT" VARCHAR2(4000),
"MOD_TIME" TIMESTAMP DEFAULT CURRENT_TIMESTAMP
)
');
END;
/
Any solution which relies on testing before creation can run into a 'race' condition where another process creates the table between you testing that it does not exists and creating it. - Minor point I know.
-- checks for table in specfic schema:
declare n number(10);
begin
Select count(*) into n from SYS.All_All_Tables where owner = 'MYSCHEMA' and TABLE_NAME = 'EMPLOYEE';
if (n = 0) then
execute immediate
'create table MYSCHEMA.EMPLOYEE ( ID NUMBER(3), NAME VARCHAR2(30) NOT NULL)';
end if;
end;
Well there are lot of answeres already provided and lot are making sense too.
Some mentioned it is just warning and some giving a temp way to disable warnings. All that will work but add risk when number of transactions in your DB is high.
I came across similar situation today and here is very simple query I came up with...
declare
begin
execute immediate '
create table "TBL" ("ID" number not null)';
exception when others then
if SQLCODE = -955 then null; else raise; end if;
end;
/
955 is failure code.
This is simple, if exception come while running query it will be suppressed. and you can use same for SQL or Oracle.
Its no need declare and count apply too.
begin
for rec in (select 1 from user_tables where table_name = 'YOUR_TABLE')
-- or
-- for rec in (select 1 from all_tables where table_name = 'YOUR_TABLE' and owner = 'YOU')
loop
execute immediate 'create table your_table as (f1 char(1))';
end loop;
end;
/
Will be good mode create check function
create or replace function this_object_exists (p_obj_name user_objects.object_name%type) return boolean
is
begin
for rec in (select 1 from user_objects where object_name = upper(p_obj_name))
loop
return true;
end loop;
return false;
end this_object_exists;
And thus use code for check exists
.
.
.
.
INDEX PARTITION
TABLE SUBPARTITION
SEQUENCE
TABLE PARTITION
PROCEDURE
LOB PARTITION
LOB
INDEX SUBPARTITION
PACKAGE
PACKAGE BODY
TYPE BODY
TRIGGER
INDEX
TABLE
VIEW
FUNCTION
SYNONYM
TYPE
JOB
...
begin
if not this_object_exists('your_table') then
execute immediate 'create table your_table as (f1 char(1))';
end if;
end;
or
begin
if this_object_exists('your_table') then
execute immediate 'drop table your_table';
end if;
execute immediate 'create table your_table as (f1 char(1))';
end;