I have two identical tables in two different databases with the same data but they have different primary keys, I need to update these so they have the same key, so what I did was making sure that none of the tables had any key in common and that there were no duplicates
UPDATE db1.dbo.Table
SET db1.dbo.Table.pcol = rightPcol.pcol
FROM db1.dbo.Table
JOIN db2.dbo.Table AS rightPcol ON db1.dbo.Table.2ndIdent = db2.dbo.Table.2ndIdent
this however results in "Violation of PRIMARY KEY Constraint. Cannot insert duplicate key in object"
when adding a where clause to not update any db1 pcol value that existed in the db2 pcol it didn't update anything at all, it does look like it tries to update with the primary key in db1 instead of db2.
any and all help is greatly appreciated!
//fixed minor spelling error :)
To be honest there isn't much to say - the error message pretty much describes what is it wrong.
You are trying to update a PK Column to a value that already exists.
I would double check to make sure that
by joining on 2ndIdent you are not creating any duplicates.
there really aren't any duplicates in the tables on DB1 and
DB2
Your SQL looks fine so it must be an issue with the data.
To check for duplicates you could use something like this:
Select 2ndIndent
From Table
Group By 2ndIdent
Having Count(2ndIndent) > 1
The "pcol" is the primary key column?
You get "Violation of primary key constraint" when the primary key from "rightPcol" is duplicate with any row in table in "db1". You should select duplicatetion from the two tables and resolve the conflict (how it reselove depends on others thing, which you didn't specified).
So the first you should select the duplications:
SELECT T1.pcol
FROM db1.dbo.Table.pcol AS T1
INNER JOIN db2.dbo.Table.pcol AS T2
ON T1.pcol = T2.pcol
Related
First, let me say that I am a newbie and that I have read many other posts with the same problem. I have a table called "AllPeople", and in that table I have an integer column called "Ethnicity", which I want to be a foreign key that points at a record in my "RefEthnicities" table. I keep getting the following message:
Unable to create relationship 'FK_AllPeople_RefEthnicities'.
The ALTER TABLE statement conflicted with the FOREIGN KEY constraint "FK_AllPeople_RefEthnicities". The conflict occurred in database "MVC-Cemeteries-Dev", table "dbo.RefEthnicities", column 'ID'.
I set up the relationship in the "AllPeople" table and told it that the primary key is the ID column in the "RefEthnicities" and the foreign key is the "Ethnicity" column in the "AllPeople" table. What am I doing wrong? My RefEthnicities table is new; no data in it.
While in design mode I set the ID field in the "RefEthnicities" table set as primary key by clicking the small box to the left of the name "ID", and down below in this same window in the column properties tab, I told it to set the index specification to "yes".
I am sure it is something simple that I am doing but I can't figure it out.
Error Message
Constraint Folder
Setting Up PK FK Link
As my limited information in the question, there 2 possibilities
NULL or Blank '' value for column Ethnicity in table AllPeople
SELECT A.Ethnicity,A.*
FROM dbo.AllPeople A
WHERE ISNULL(A.Ethnicity,'')=''
Some values column Ethnicity in table AllPeople don't have parent in column ID in table RefEthnicities
SELECT A.Ethnicity,R.ID, *
FROM dbo.AllPeople A
LEFT JOIN RefEthnicities R
ON A.Ethnicity=R.ID
WHERE R.ID IS NULL
If you get any rows in two queries, then you need to fix data in column Ethnicity in table AllPeople.
Read
Ok this still makes no sense. If I create two brand new tables with the following:
table1
ID primary key int not nullable
value varchar
table2FK
table2
ID primary key int not nullable
value varchar
and in table1 I make a relationship between table2FK and Table2.ID, it works perfect with no data saved in the tables. If I use the exact same process in my AllPeople and RefEthnicicties tables, I get the error. This makes no sense. What am I missing?
adam
That fixed it. many thanks. I had a record in my AllPeople table for ethnicity that had a value of 0. Since I didn't have a record in the RefEthnicity Table with an ID of 0, it was telling me that I couldn't do this.
adam
So after googling this simple question, I could have not find an answer anywhere. I only have very basic database knowledge, and I need a query in Oracle to properly select a row given a table name and a primary key. Most examples I have found all find rows based of a row number or rowID (is that the same as primary key?).
Any help on this would be greatly appreciated.
Do you have the primary key column and the value you want to query? Where or what exactly did you search for? This is a very basic SELECT statement in any relational database:
SELECT *
FROM table_name
WHERE primary_key_column = primary_key_value
Unless, of course, I didn't understand the question.
A primary key is a unique identifier for a row in a table. Each row will have a primary key that is different from all other rows. This key can be one value, such as a rowID, or it can be a composite value (multiple columns used as a primary key because there may not be a need for an extra column only to store a rowID).
#tilley31 above shows a great example of how to search for a specific row in a table. If the primary key was composite;
SELECT *
FROM table_name
WHERE primary_key_column1 = primary_key_value1
AND primary_key_column2 = primary_key_value2
ROWID is a pseudocolumn that returns the address of a row and is usually unique, exception being where more than one table is stored in a same cluster then those tables rows can share the same rowid. ROWID is implicitly given by the oracle to rows.
Primary key uniquely identifies a row at a table level and is created by the user who created the table.
Getting the ROWID of a Row
SELECT ROWID,FIELDNAME FROM ABC;
Getting the PRIMARY Key of a table
SELECT * FROM USER_CONSTRAINTS WHERE TABLE_NAME='YOUR_TABLENAME'
AND CONSTRAINT_TYPE='P';
I guess you are intent to dynamically choose table and where clauses in query (?)
If this is what you want to do then answer is No. Its not possible just through query. You could achieve it through pl/sql. and if you must have this as a query consider using a table function like below -
SELECT * FROM TABLE(func('TABLE_NAME','WHERE_CONDITION'))
Check out this link: https://oracle-base.com/articles/misc/pipelined-table-functions
Again this requires you to have preset output columns (COLUMN1, COLUMN2 etc). You will not be able to select exact column names from table.
Overall this is going to be messy.
Background Information
For some reason, while inserting a huge data into multiple tables from xml, my primary keys are shifted by an offset.. (Maybe because of multiple failed attempts :P)
I have two tables.. tableA and tableB. They are in one-to-may relationship.
tableA is the parent table and has the Primary key column ...say DataIndex.
now DataIndex has come out like this..
685, 686, 687... and so on.
and corresponding values present in the child table i.e TableB are the same.
Problem
How do I shift the values up so that DataIndex start from 1, 2, 3..and so on; In both tables ?
I'm assuming that the primary key is actually an identity column that auto-increments itself upon insertion. What you will need to do is 'reseed' the identity column. You can do this by renaming the table, create a duplicate table with the original name, then inserting the data from the old table to the new one (the primary key field will be reset and will auto-increment from 1 again). When doing the insertion, make sure to include the old primary key value as an additional column for reference in the other tables.
To match up the related table, all you will need to do is do an UPDATE and join to your new table on the old primary key value:
UPDATE tableB SET
PRIMARYKEYCOLUMN = tableA.PRIMARYKEYCOLUMN
FROM tableA
WHERE
tableA.OLDPRIMARYKEYCOLUMN = tableB.PRIMARYKEYCOLUMN
I would do the following:
construct a list of Foreign Keys pointing to your PK;
ALTER all FKs, adding ON UPDATE CASCADE clause. This step might not work for some databases, you might need to DROP and CREATE constraint again;
Find the smallest current PK values, like: SELECT min(id) FROM tableA;
Refresh PK values: UPDATE tableA SET id = id - min_id + 1;
Remove ON UPDATE CASCADE clause.
Note, that depending on the tableA size and the database engine you're using, it might be faster and easier to completely rebuild the table to avoid bloat of data files.
Remove PK
Walk through records eith DB CURSOR or write a script on any language sequentally reading and changing id's
Restore PK
Setup correct identity seed for the PK
Changing seed might involve identity column drop and recreate.
This question have been asked by several people but my problem seems to be different.
Actually I have to merge same structured tables from different databases in postgresql into a new DB. What I am doing is that I connect to remote db using dblink, reads that table in that db and insert it into the table in the current DB like below
INSERT INTO t_types_of_dementia SELECT * FROM dblink('host=localhost port=5432 dbname=snap-cadence password=xxxxxx', 'SELECT dementia_type, snapid FROM t_types_of_dementia') as x(dementia_type VARCHAR(256),snapid integer);
First time this query runs fine, but when I run it again or try to run it with some other remote database's table: it gives me this error
ERROR: duplicate key value violates unique constraint
"t_types_of_dementia_pkey"
I want that this new tables gets populated by entries of others tables from other dbs.
Some of the solutions proposed talks about sequence, but i am not using any
The structure of the table in current db is
CREATE TABLE t_types_of_dementia(
dementia_type VARCHAR(256),
snapid integer NOT NULL,
PRIMARY KEY (dementia_type,snapid)
);
P.S. There is a specific reason why both the columns are used as a primary key which may not be relevant in this discussion, because same issue happens in other tables where this is not the case.
As the error message tells you - you can not have two rows with the same value in the columns dementia_type, snapid since they need to be unique.
You have to make sure that the two databases has the same values for dementia_type, snapid.
A workaround would be to add a column to your table alter table t_types_of_dementia add column id serial generated always and use that as primary key instead of your current.
I need to make some changes to a SQL Server 2008 database.
This requires the creation of a new table, and inserting a foreign key in the new table that references the Primary key of an already existing table. So I want to set up a relationship between my new tblTwo, which references the primary key of tblOne.
However when I tried to do this (through SQL Server Management Studio) I got the following error:
The columns in table 'tblOne' do not
match an existing primary key or
UNIQUE constraint
I'm not really sure what this means, and I was wondering if there was any way around it?
It means that the primary key in tblOne hasn't been properly declared - you need to go to tblOne and add the PRIMARY KEY constraint back onto it.
If you're sure that tblOne does have a PRIMARY KEY constraint, then maybe there are multiple tblOne tables in your DB, belonging to different schemas, and your references clause in your FK constraint is picking the wrong one.
If there's a composite key (which your comment would indicate), then you have to include both columns in your foreign key reference also. Note that a table can't have multiple primary keys - but if it has a composite key, you'll see a key symbol next to each column that is part of the primary key.
If you have a composite key the order is important when creating a FK, and sometimes the order is not how it is displayed.
What I do is go to the Keys section of the table1 and select script primary key as create to clipboard and then create FK using the order as shown in script
I've had this situation that led me to this topic. Same error but another cause. Maybe it will help someone.
Table1
ColA (PK)
ColB (PK)
ColC
Table2
ID (PK)
ColA
COLB
When trying to create foreign key in Table2 I've choose values from combobox in reverse order
Table1.ColB = Table2.ColB
Table1.ColA = Table2.ColA
This was throwing me an error like in topic name. Creating FK keeping order of columns in Primary key table as they are, made error disappear.
Stupid, but.. :)
If you still get that error after you have followed all advice from the above answers and everything looks right.
One way to fix it is by Removing your Primary keys for both tables, Save, Refresh, and add them again.
Then try to add your relationship again.
This Error happened with me When I tried to add foreign key constraint starting from PrimaryKey Table
Simpy go to other table and and create this foreign key constraint from there (foreign key Table)
This issue caught me out, I was adding the relationship on the wrong table. So if you're trying to add a relationship in table A to table B, try adding the relationship in table B to table A.
That looks like you are trying to create a foreign key in tblTwo that does not match (or participate) with any primary key or unique index in tblOne.
Check this link on MSDN regarding it. Here you have another link with a practical case.
EDIT:
Answwering to your comment, I understand you mean there are 2 fields in the primary key (which makes it a composite). In SQL it is not possible to have 2 primary keys on the same table.
IMHO, a foreign key field should always refer to a single register in the referenced table (i.e. the whole primary key in your case). That means you need to put both fields of the tblOne primary key in tblTwo before creating the foreign key.
Anyway, I have investigated a bit over the Internet and it seems SQL Server 2008 (as some prior versions and other RDBMS) gives you the possibility to reference only part of the primary key as long as this part is a candidate key (Not Null and Unique) and you create an unique constraint on it.
I am not sure you can use that in your case, but check this link for more information on it.
I have found that the column names must match.
Example:
So if tblOne has id called categoryId a reference in tblTwo must also be called categoryId.
_tblname, primary key name, foreign key_
tblOne, "categoryId", none
tblTwo, "exampleId", "categoryId"
I noticed this when trying to create foreign key between 2 tables that both had the column name "id" as primary key.
If nothing helps, then this could be the reason:
Considering this case:
Table A:
Column 1 (Primary Key)
Column 2 (Primary Key)
Column 3
Column 4
Table B:
Column a (Primary Key)
Column b
Column c
when you are defining a dependency B to A, then you are forced to respect the order in which the primaries are defined.
That's mean your dependency should look like this:
Table A Table B
Column 1 Column b
Column 2 Column c
AND NOT:
Table A Table B
Column 2 Column c
Column 1 Column b
then this will lead to the error you are encountering.
I've found another way to get this error. This can also happen if you are trying to make a recursive foreign key (a foreign key to the primary key in the same table) in design view in SQL Management Studio. If you haven't yet saved the table with the primary key it will return this message. Simply save the table then it will allow you to create the foreign key.
If you have data in your tables this could be the issue.
In my case I had some data in the Account table that I loaded at 3 pm, and some data in Contact table that I loaded at 3:10 pm, so Contact table had some values that weren't in my Account table yet.
I ended up deleting these values from the contact table and then managed to add a key without any problems.
Kindly also see that there are no existing data inside the table where the primary key is defined while setting the foreign key with another table column.
this was the cause of the error in my case.
I had to take backup empty the table set the relationship and then upload the data back.
sharing my experience
Was using ms sql smss