SQL & PL/SQL :: Execution Model For Triggers And Integrity Constraint Checking
Sep 7, 2010
URL....Topic: The Execution Model for Triggers and Integrity Constraint Checking
Oracle uses the following execution model to maintain the proper firing sequence of multiple triggers and constraint checking:
1.Run all BEFORE statement triggers that apply to the statement.
2.Loop for each row affected by the SQL statement.
a.Run all BEFORE row triggers that apply to the statement.
b.Lock and change row, and perform integrity constraint checking. (The lock is not released until the transaction is committed.)
c.Run all AFTER row triggers that apply to the statement.
3.Complete deferred integrity constraint checking.
4.Run all AFTER statement triggers that apply to the statement.
i have an understanding about Integrity constraint checking and the trigger execution sequence, which i decsribe below.
Integrity constraint are restiction on DML operation performed by the user. When a user deletes or updates or inserts a rows in a table then oracle performs certain checking to see that the data which is effecting the row abide certain rules. There are certain per-defined set or rules that can be applied on a table such as PRIMARY KEY, FORIEGN KEY, UNIQUE, CHECK, NOT NULL etc, user-defined rules can be applied on tables by using Triggers.
In both the cases the Integrity Constraint Checking is deferred until the complete execution of the statement. All rows are inserted first, then all rows are checked for constraint violations.
So when i see the trigger execution model the following steps are performed by oracle, Oracle uses the following execution model to maintain the proper firing sequence of multiple triggers and constraint checking..This is what the Oracle Documentation Library says [extract from Oracle Database Concepts 10g Release 1 (10.1)].
1. Run all BEFORE statement triggers that apply to the statement.
2. Loop for each row affected by the SQL statement. a.Run all BEFORE row triggers that apply to the statement. b.Lock and change row, and perform integrity constraint checking. (The lock is not released until the transaction is committed.) c.Run all AFTER row triggers that apply to the statement.
4.Run all AFTER statement triggers that apply to the statement.
As for step 3 here the checking of the constraints for the statement is performed which where defered till the complete execution of the statement, then what is done in step 2b? what constraints are checked there?
Can I apply Referential Integrity to only selected rows of a particular column? This is the reference key to the primary key to another table. But, the issue is, this reference column is not having mandatory data for all the rows. So, whenever this is null, I dont want it to be referred by parent table.
Referential Integrity is very important in Oracle database. Consider a scenario where constraints were applied to a database but never enforced on. Only application code was leveraged over the past 1 year to manage this logic.
Over the course of the year there might have been lot of Row Violations which might have led to Data Inconsistency Issues.Do we have a Script, Tools in Oracle which flag all row level violations with referential integrity now being turned on.
i am running the query from which i am getting below mentioned error how can i find the record which is not there in parent table ora02291 integrety constrain violated and parent key not found.
I have created a amortization SELECT statement that amortizes loans based upon a table of loan information. The problem is this: when I run an ITERATION on numbers, the select statement returns a value but the ITERATION seems to be reading zero. This leads to a bunch of zeroes in the resultant table.
P C_USER1 C_USER9 C_USER11 C_USER10 C_B1 C_B2 C_BUDGET C_USER12 0 Jones 131828.81 3.348 72 0 0 131828.81 2023.55 0 Jones 131828.81 3.348 1 367.8 -367.8 132196.61 2023.55
As you can see, in column C-B2, despite referencing the column C_USER12 which should have 2023.55 as a value in it, it is returning the mirror opposite of C_B1 which leads me to believe that the system is reading a ZERO in the column despite displaying 2023.55.
We use apex and my professor wants us to import a table model into apex. everytime i try and import my table it says "your export file is not supported". i asked my professor what to do and he said "You should gen a ddl file from designer. Then use that to upload into apex and then run.
I have one report consist of two user parameters like FROMDATAE and TODATE and two queries in data model..
The 1st query is..
SELECT WONO,MCV_DATE,QTY FROM MCSHOP1 WHERE MCV_DATE BETWEEN :FROMDATE AND :TODATE;
It created two user parameters.ie FROMDATE and TODATE.
And 2nd query like this
SELECT MCVN FROM MCSHOP1 WHERE WONO=:WONO OR WONO LIKE 'RW%'||:WONO;
I dont know how to make 2nd query in data model. becoz the WONO will come from 1st query and LIKE command is there..But I tried in formula Column....but it returns more than one row...
i want to get table name, constraint name, constraint type with join processes in string type. this is what i want: alter table tablename add constraint constraintname constrainttype(columnname)
We would like to used Oracle secure backup using SAS interface on an IBM Autoloader Model TS-2900. Would it be possible to configure oracle secure backup using SAS?
I am trying to use model clause to get comma separate single row for multiple rows. My scenario is like this:
SQL> desc test1 Name Null? Type ----------------------------------------------------- -------- ------------------------------------ ID NUMBER VALUE CHAR(6)
SQL> select * from test1 order by id;
ID VALUE ---------- ------ 1 Value1 2 Value2 3 Value3 4 Value4 5 Value4 6 7 value5 8
The query that I have is: SQL> with t as 2 ( select distinct substr(value,2) value 3 from test1 4 model 5 ignore nav 6 dimension by (id) 7 measures (cast(value as varchar2(100)) value) 8 rules 9 ( value[any] order by id = value[cv()-1] || ',' || value[cv()] 10 ) 11 ) 12 select max(value) oneline 13 from t;
For applications and Timesten databases on the same server we can use direct model to gain the base performance. But I want to know that how big heap size of JVM to be set for my java application when enabling direct model?
Does my application need more head memory when direct model than other local communication protocols, such as Unix domain socket or IPC? Supposing my Timesten database takes 12GB memory from OS, does it mean I need specify the same size for JVM heap(-Xmx12G)?
We are attempting to configure/use OEM (Oracle 10.2.0.4) on Solaris, and when logging in to OEM we are directed to the Database Down page, stating Enterprise Manager is unable to connect to the database instance, but showing all the components as up/open. After checking the log, I found the following error:
IO exception: Unknown Encryption or Data Integrity algorithm
I checked the settings in emoms.properties and compared the encryption parameters to those in our SQLNet file, and all match up. We are NOT using Grid Control, just db control connecting to 1 instance.
What is the best practices to maintain aggregate columns? Suppose I have the following 2 tables:
DROP TABLE TEST.ORDERS_DET_T; DROP TABLE TEST.ORDERS_T; CREATE TABLE TEST.ORDERS_T ( ID NUMBER NOT NULL PRIMARY KEY, ORDER_CODE VARCHAR2(100) NOT NULL,
[code]....
I want the following test script to act int the way, described in comments. Basically this means that the sum of TEST.ORDERS_DET_T.ORDER_DET_SUMA must be equal to TEST.ORDERS_T.ORDER_SUMA after transaction commits.
INSERT INTO TEST.ORDERS_T(ID, ORDER_CODE, ORDER_SUMA) VALUES(1,'FRUITS',100); INSERT INTO TEST.ORDERS_DET_T(ID, ORDERS_T_ID, ORDER_DET_CODE, ORDER_DET_SUMA) VALUES(2,1,'APPLES',40); INSERT INTO TEST.ORDERS_DET_T(ID, ORDERS_T_ID, ORDER_DET_CODE, ORDER_DET_SUMA) VALUES(3,1,'PEAT',60); COMMIT; --SHOULD BE OK, 40+60=100
[code]....
P.S. Creating views based on ORDERS_T and ORDERS_DET_T are not an option, if the user would still be allowed to modify data in tables (as in test scenarios). This is because of current business situation, where the client has 2 teams (outsourcing for back-office solution and insourcing for web solution) that are accessing/modifying the data in the same tables.
Can I apply Referential Integrity to only selected rows of a particular column? This is the reference key to the primary key to another table. But, the issue is, this reference column is not having mandatory data for all the rows. So, whenever this is null, I dont want it to be referred by parent table.
no, and it makes no sense to do so either
We have an appointment form in our HIS, where patients take telephonic appointment. That time they may not know their user id given by hospital. So, it remains blank & name is entered manually. But if the user-id is entered, it must fetch patient name from the master.
The candidate key must be unique within its domain.The candidate key can not hold NULL values.
MRREGISTRTNHD is a patient master & has a primary key named N_PATIENTMR_ID. HLTHCHKAPPOINTHD is a appointment table & has a foreign key named N_PATIENTMR_ID which references N_PATIENTMR_ID of MRREGISTRTNHD.
Also, N_PATIENTMR_ID of HLTHCHKAPPOINTHD is not a unique key & it can contain null values also. I want to define constraint or any other method such that only the not null values are referenced to the master i.e. it should validate in the master. And null values should skip this reference.
Now, what happens is due to this constraint, when I'm trying to edit & update the rows having null value in N_PATIENTMR_ID, it gives the following error.
ORA-02291: Integrity constraint (SYS_C007145) violated - parent key not found
So, can I give some condition in the above constraint saying, apply this constraint to table HLTHCHKAPPOINTHD only having the not-null values in N_PATIENTMR_ID coulmn?
I've an Oracle Table which has around 300 columns. I've a requirement to split this single table into two tables (150 columns each) by a foreign key.
Now I want to know how to maintain the data integrity while I insert the data into two tables. which means each table should have equal number of rows as we insert the 300 columns data into tables each at a time.
I install oracle 11g2 on centos, in prerequisite checks step ,oracle database show this failed "Oracle Restart integrity Failed", I don't know what should i do ?
I'm trying to add edmx file in my project for first time. I want to choose the oracle provider ODP.net but cannot find Oracle in the data source list. I have oracle 11g installed , odp and odt installed and can access it from the solution as well. I saw the Oracle listed under data source when I tried to connect the solution to the database through server explorer. The solution is connected to Oracle database through ODP.
I am using Datapump import using database link to import an entire schema from another Server but it gives issues with constraints.I tried to first only import the metadata and then disable the constraints and import data and enable constraint but in this case the temp tablespace keeps filling up and i am out of space. Is there any method to do a full import including constraints and indexes.
Am creating a table based on some integrity constraints, but it's not working.
CREATE TABLE member ( member_id NUMBER(10), last_name VARCHAR2(25) NOT NULL, first_name VARCHAR2(25),
[code],,,
Error:
Error report: SQL Error: ORA-02270: no matching unique or primary key for this column-list 02270. 00000 - "no matching unique or primary key for this column-list" *Cause: A REFERENCES clause in a CREATE/ALTER TABLE statement gives a column-list for which there is no matching unique or primary key constraint in the referenced table. *Action: Find the correct column names using the ALL_CONS_COLUMNScatalog view
I am trying to install Oracle Database 11gR2 database on Oracle Grid 11gR2. I successfully installed Grid without errors. However, when installing the database, I got an OLR Integrity error during the prerequisit Check
OLR Integrity - This test checks the integrity of OLR on the local node. Expected Value : n/a Actual Value : n/a List of errors: - Permissons of file "/u01/app/oracle/product/11.2.0/grid/cdata/localhost/localhost.olr" did not match the expected value. [Expected = "0600"; Found = "0660"] - Cause: Cause of Problem Not Available - Action: User Action Not Available.
We have a problem where a data load script has caused data in one of our tables to be incorrectly loaded. Instead of loading the parent row, it has loaded an offest that was assigned by the application.
Which is the best way to check whether a record exists.
DECLARE l_count NUMBER; BEGIN SELECT COUNT(*) INTO l_count FROM emp WHERE empno=7839; IF l_count=1 THEN dbms_output.put_line('exists'); ELSE dbms_output.put_line('not exists'); END IF; END;
