I am trying to debug an old foxpro app and I am seeing the following a query -
select db.column1, ..., DELETED() as columnname from ....
My question is as follows - what does the DELETED() in the sql statement mean? is the a foxpro function, or is it most likely a custom function that appears in the code somewere?
thanks.
In addition to what Tom Brothers said, FoxPro has a SET DELETED [ON/OFF] environment setting that controls whether or not FoxPro commands process records that are marked for deletion. This setting is scoped to the data session.
* Create a table with 3 records, delete the 2nd record.
CREATE TABLE "DeleteTest.DBF" (pk I)
INSERT INTO "DeleteTest" (pk) VALUES (1)
INSERT INTO "DeleteTest" (pk) VALUES (2)
INSERT INTO "DeleteTest" (pk) VALUES (3)
DELETE FROM "DeleteTest" WHERE (pk = 2)
* Allow VFP to access deleted records, the result will be 3 records.
SET DELETED OFF
SELECT pk, DELETED() AS delete_flag FROM "DeleteTest"
* Prevent VFP from accessing deleted records, the result will be 2 records.
SET DELETED ON
SELECT pk, DELETED() AS delete_flag FROM "DeleteTest"
DELETED() is a foxpro command that returns a logical value that indicates if the row has been deleted.
Related
I have two instances of the same database, but data is only committed to the "original" one. I need to copy inserted data from certain tables and commit them to the same tables in the second DB automatically. How can I do it?
I've already created synonyms for the tables in the second DB on original and within a specially prepared trigger I tried to use INSERT INTO ... statement with :new. but it is causing the data to not be committed anywhere and I receive Oracle Errors like:
ORA-02291: integrity constraint (PRDBSHADOW.FK_ED_PHY_ENT) violated.
Here is my trigger code
create or replace TRIGGER INS_COPY_DATA
AFTER INSERT ON ORIGDB.TABLE_A
REFERENCING NEW AS NEW OLD AS OLD
FOR EACH ROW
BEGIN
insert into COPY_TABLE_A(val1,val2,val3,val4) values (:new.val1, :new.val2, :new.val3, :new.val4);
END;
I think the entry in parent table is missing here. At least the FK ending of constraint is telling me so.
It means you need to insert first all the data into a "parent" table in order to be able to insert records in a "child".
For example the table auto_maker is having 3 rows only: Audi, Peugeot, and Honda.
Another table named "model" has 2 columns "maker" and "model". "maker" is a foreign key referencing to the "auto_maker" table.
It means in the models table are only the records allowed whose "maker" column value exists in "auto_maker" table.
In other words only these are available:
maker model
Audi A4
Peugeot 308
Honda Accord
Of course you can enter every model you wish, but "maker" value has to exist in the auto_maker table.
This is what probably happen - the trigger tries to insert a data in a column which is referencing to a "parent" table and the :new value just doesn't exist.
The following script will let you know what table you need to fill first.
select aic.index_owner, aic.table_name, aic.column_name
from all_constraints uc,
all_ind_columns aic
where aic.INDEX_NAME = uc.r_constraint_name
and uc.table_name = 'TABLE_A'
and uc.constraint_type = 'R';
If the query returns something just create similar triggers on those tables with similar logic you already have
I read a lot about it but didn't found any help on that.
My Situation:
I've two database tables which belongs together. This tables I want to query with EntityFramework. Because Table B contains for EntityFramework the discriminator (for choosing the correct class for Table A) I've created a View which Joins Table A and Table B.
This join is quite simple. But: I want also to store data with that View. The issue is, that EntityFramework also wants to store the discriminator. But this isn't possible because it would update/insert into two tables.
So I've tried to create an "Instead of" trigger to just update/insert Table A (because Table B doesn't matter and will never be updated).
When I created the trigger - everything fine. If I insert something with an SQL Statement - everything is fine. But: If I'm inserting directly in the View (using Oracle SQL Developer) it throws the Exception as below:
ORA-22816 (unsupported feature with RETURNING clause).
If I do the same with EntityFramework I get the same error. Can someone help me?
Below my Code:
Table A and Table B:
CREATE Table "TableA"
(
"ID" Number NOT NULL,
"OTHER_VALUESA" varchar2(255),
"TableB_ID" number not null,
CONSTRAINT PK_TableA PRIMARY KEY (ID)
);
CREATE Table "TableB"
(
"ID" Number NOT NULL,
"NAME" varchar2(255),
"DISCRIMINATOR" varchar2(255),
CONSTRAINT PK_TableB PRIMARY KEY (ID)
);
The Joined View:
Create or Replace View "JoinTableAandB"
(
"ID",
"OTHER_VALUESA",
"TableB_ID",
"DISCRIMINATOR"
) AS
select tableA.ID, tableA.OTHER_VALUESA, tableA.TableB_ID, tableB.DISCRIMINATOR
from TABLEA tableA
inner join TABLEB tableB on tableA.TableB_ID = tableB.ID;
And finally the Trigger:
create or replace TRIGGER "JoinTableAandB_TRG"
INSTEAD OF INSERT ON "JoinTableAandB"
FOR EACH ROW
BEGIN
insert into TABLEA(OTHER_VALUESA, TABLEB_ID)
values (:NEW.OTHER_VALUESA, :NEW.TABLEB_ID);
END;
I've also tried it (to verify if the insert is correct just to enter "NULL" into the trigger instead of insert. But got the same error message.
Does anybody know how to solve this? Or does anybody have a good alternative (better Idea)?
Thanks!
Note: I've also defined a sequence for TableA's ID so that it will be generated automatically.
// Edit:
I found a possible Solution for MS SQL:
https://stackoverflow.com/a/26897952/3598980
But I don't know how to translate this to Oracle... How can I return something from a trigger?
Note: I've also defined a sequence for TableA's ID so that it will be generated automatically.
In EF StoreGenerated keys in Oracle are incompatible with INSTEAD OF triggers. EF uses a RETURNING clause to output the store generated keys, which doesn't work with INSTEAD OF triggers.
This question already has answers here:
How to create id with AUTO_INCREMENT on Oracle?
(18 answers)
Closed 7 years ago.
I want to add a new auto increment primary column to a existing table which has data. How do I do that?
I first added a column and then try to add a sequence after that, I lost how to insert and make that column as primary key.
Say your table is called t1 and your primary-key is called id
First, create the sequence:
create sequence t1_seq start with 1 increment by 1 nomaxvalue;
Then create a trigger that increments upon insert:
create trigger t1_trigger
before insert on t1
for each row
begin
select t1_seq.nextval into :new.id from dual;
end;
If you have the column and the sequence, you first need to populate a new key for all the existing rows. Assuming you don't care which key is assigned to which row
UPDATE table_name
SET new_pk_column = sequence_name.nextval;
Once that's done, you can create the primary key constraint (this assumes that either there is no existing primary key constraint or that you have already dropped the existing primary key constraint)
ALTER TABLE table_name
ADD CONSTRAINT pk_table_name PRIMARY KEY( new_pk_column )
If you want to generate the key automatically, you'd need to add a trigger
CREATE TRIGGER trigger_name
BEFORE INSERT ON table_name
FOR EACH ROW
BEGIN
:new.new_pk_column := sequence_name.nextval;
END;
If you are on an older version of Oracle, the syntax is a bit more cumbersome
CREATE TRIGGER trigger_name
BEFORE INSERT ON table_name
FOR EACH ROW
BEGIN
SELECT sequence_name.nextval
INTO :new.new_pk_column
FROM dual;
END;
Snagged from Oracle OTN forums
Use alter table to add column, for example:
alter table tableName add(columnName NUMBER);
Then create a sequence:
CREATE SEQUENCE SEQ_ID
START WITH 1
INCREMENT BY 1
MAXVALUE 99999999
MINVALUE 1
NOCYCLE;
and, the use update to insert values in column like this
UPDATE tableName SET columnName = seq_test_id.NEXTVAL
You can use the Oracle Data Modeler to create auto incrementing surrogate keys.
Step 1. - Create a Relational Diagram
You can first create a Logical Diagram and Engineer to create the Relational Diagram or you can straightaway create the Relational Diagram.
Add the entity (table) that required to have auto incremented PK, select the type of the PK as Integer.
Step 2. - Edit PK Column Property
Get the properties of the PK column.
You can double click the name of the column or click on the 'Properties' button.
Column Properties dialog box appears.
Select the General Tab (Default Selection for the first time).
Then select both the 'Auto Increment' and 'Identity Column' check boxes.
Step 3. - Additional Information
Additional information relating to the auto increment can be specified by selecting the 'Auto Increment' tab.
Start With
Increment By
Min Value
Max Value
Cycle
Disable Cache
Order
Sequence Name
Trigger Name
Generate Trigger
It is usually a good idea to mention the sequence name, so that it will be useful in PL/SQL.
Click OK (Apply) to the Column Properties dialog box.
Click OK (Apply) to the Table Properties dialog box.
Table appears in the Relational Diagram.
This question already has answers here:
How to create id with AUTO_INCREMENT on Oracle?
(18 answers)
Closed 7 years ago.
I want to add a new auto increment primary column to a existing table which has data. How do I do that?
I first added a column and then try to add a sequence after that, I lost how to insert and make that column as primary key.
Say your table is called t1 and your primary-key is called id
First, create the sequence:
create sequence t1_seq start with 1 increment by 1 nomaxvalue;
Then create a trigger that increments upon insert:
create trigger t1_trigger
before insert on t1
for each row
begin
select t1_seq.nextval into :new.id from dual;
end;
If you have the column and the sequence, you first need to populate a new key for all the existing rows. Assuming you don't care which key is assigned to which row
UPDATE table_name
SET new_pk_column = sequence_name.nextval;
Once that's done, you can create the primary key constraint (this assumes that either there is no existing primary key constraint or that you have already dropped the existing primary key constraint)
ALTER TABLE table_name
ADD CONSTRAINT pk_table_name PRIMARY KEY( new_pk_column )
If you want to generate the key automatically, you'd need to add a trigger
CREATE TRIGGER trigger_name
BEFORE INSERT ON table_name
FOR EACH ROW
BEGIN
:new.new_pk_column := sequence_name.nextval;
END;
If you are on an older version of Oracle, the syntax is a bit more cumbersome
CREATE TRIGGER trigger_name
BEFORE INSERT ON table_name
FOR EACH ROW
BEGIN
SELECT sequence_name.nextval
INTO :new.new_pk_column
FROM dual;
END;
Snagged from Oracle OTN forums
Use alter table to add column, for example:
alter table tableName add(columnName NUMBER);
Then create a sequence:
CREATE SEQUENCE SEQ_ID
START WITH 1
INCREMENT BY 1
MAXVALUE 99999999
MINVALUE 1
NOCYCLE;
and, the use update to insert values in column like this
UPDATE tableName SET columnName = seq_test_id.NEXTVAL
You can use the Oracle Data Modeler to create auto incrementing surrogate keys.
Step 1. - Create a Relational Diagram
You can first create a Logical Diagram and Engineer to create the Relational Diagram or you can straightaway create the Relational Diagram.
Add the entity (table) that required to have auto incremented PK, select the type of the PK as Integer.
Step 2. - Edit PK Column Property
Get the properties of the PK column.
You can double click the name of the column or click on the 'Properties' button.
Column Properties dialog box appears.
Select the General Tab (Default Selection for the first time).
Then select both the 'Auto Increment' and 'Identity Column' check boxes.
Step 3. - Additional Information
Additional information relating to the auto increment can be specified by selecting the 'Auto Increment' tab.
Start With
Increment By
Min Value
Max Value
Cycle
Disable Cache
Order
Sequence Name
Trigger Name
Generate Trigger
It is usually a good idea to mention the sequence name, so that it will be useful in PL/SQL.
Click OK (Apply) to the Column Properties dialog box.
Click OK (Apply) to the Table Properties dialog box.
Table appears in the Relational Diagram.
I have this table in an Oracle DB which has a primary key defined on 3 of the data columns. I want to drop the primary key constraint to allow rows with duplicate data for those columns, and create a new column, 'id', to contain an auto-incrementing integer ID for these rows. I know how to create a sequence and trigger to add an auto-incrementing ID for new rows added to the table, but is it possible to write a PL/SQL statement to add unique IDs to all the rows that are already in the table?
Once you have created the sequence:
update mytable
set id = mysequence.nextval;
If you're just using an integer for a sequence you could update the id with the rownum. e.g.
update
table
set id = rownum
You then need to reset the sequence to the next valid id.
Is this what you need?
UPDATE your_table
SET id = your_seq.nextval;
This assumes you don't care what order your primary keys are in.
First you should check your PCTFREE... is there enough room for every row to get longer?
If you chose a very small PCTFREE or your data has lots of lenght-increasing updates, you might begin chaining every row to do this as an update.
You almost certainly better to do this as a CTAS.
Create table t2 as select seq.nextval, t1.* from t1.
drop t1
rename t2 to t1.