I'm using C# and Microsoft.Jet.OLEDB.4.0 provider to insert rows into an Access mdb.
Yes, I know Access sucks. It's a huge legacy app, and everything else works OK.
The table has an autonumber column. I insert the rows, but the autonumber column is set to zero.
I Googled the question and read all the articles I could find on this subject. One suggested inserting -1 for the autonumber column, but this didn't work. None of the other suggestions I could find worked.
I am using OleDbParameter's, not concatenating a big SQL text string.
I've tried the insert with and without a transaction. No difference.
How do I get this insert to work (i.e. set the autonumber column contents correctly)?
Thanks very much in advance,
Adam Leffert
In Access it is possible to INSERT an explicit value into an IDENTITY (a.k.a. Automnumber) column. If you (or your middleware) is writing the value zero to the IDENTITY column and there is no unique constraint on the IDENTITY column then that might explain it.
Just to be clear you should be using the syntax
INSERT INTO (<column list>) ...
and the column list should omit the IDENTITY column. Jet SQL will allow you to omit the entire column list but then implicitly include the IDENTITY column. Therefore you should use the INSERT INTO () syntax to explicitly omit the IDENTITY column.
In Access/Jet, you can write explicit values to the IDENTITY column, in which case the value will obviously not be auto-generated. Therefore, ensure both you and your middleware (ADO.NET etc) are not explicitly writing a zero value to the IDENTITY column.
BTW just for the IDENTITY column in the below table will auto-generate the value zero every second INSERT:
CREATE Table Test1
(
ID INTEGER IDENTITY(0, -2147483648) NOT NULL,
data_col INTEGER
);
When doing the insert, you need to be sure that you are NOT specifying a value for the AutoNumber column. Just like in SQL Server you don't insert a value for an identity column.
Related
Is there an easy way to overwrite a row that contains a unique index, rather than just failing?
Or do I need to do an update and/or a delete then add.
It would be nice to have a setting when trying to add a row that would violate a unique index constraint it would replace the exist row that matches that the unique index.
My db is defined on Azure using a Core (SQL) API. Any thoughts?
Use UpsertItemAsync(). This will work.
I am implementing SCD Type2 through Data Flow. I having created a Parameter in it where I will pass a column name and this Parameter I am using in Sink Transformation in Key Column.
Passing a parameter in Key Column in Data Flow
I have selected the Add Dynamic Content and then Parameter, after that I selected the parameter I have created in Data Flow. Then it shows like "$Key_col".
But when I run the pipeline it gives me an error-
{"message":"at Sink 'sink1'(Line 56/Col 6): Column operands are not allowed in literal expressions. Details:at Sink 'sink1'(Line 56/Col 6): Column operands are not allowed in literal expressions","failureType":"UserError","target":"Update_Existing_Records","errorCode":"DFExecutorUserError"}
Can anyone please tell me how resolve this error or any workaround for this Problem.
Yes, this work. You just need to put single quotes around the parameter value like this:
"'$Key_col'"
I'm using double-quotes for string interpolation in this solution, so paste it in your expression exactly as that.
Key column doesn't support set with parameter. You only can choose the exist column in sink.
The column name that you pick as the key here will be used by ADF as part of the subsequent update, upsert, delete. Therefore, you must pick a column that exists in the Sink mapping. If you wish to not write the value to this key column, then click "Skip writing key columns".
Please reference: Mapping data flow properties.
The parameter Key_col is not exist in the sink, even if it has the same name.
Update:
Data Flow parameter:
If we want to using update, we must add an Alter row active:
Sink, key column choose exist column 'name':
Pipeline runs successful:
Hope this helps.
I want to retrieve all items within a specific column of a table.
In this scenario, I have 2 tables, The first table contains a primary key, and the second table contains a foreign key. a 1 to many relationship is set up for the tables respectively.
I want a function/way of retrieving all items within a column in table 2 that has a foreign key that matches the primary key in table 1.
One way of doing this is through a VLOOKUP, though surely through using DAX, or some other function set, I can exploit the relationship I have made in the DataModel to make this easier for me to do.
Why don't you just get the required data from the DB with a proper SELECT statement? Something like
SELECT column
FROM t1, t2
WHERE t1.key = t2.fkey
AND t1.key = 'whatever you search for';
Then you should get the data you want.
The CQL3 specification description of the UPDATE statement begins with the following paragraph:
The UPDATE statement writes one or more columns for a given row in a
table. The (where-clause) is used to select the row to update and must
include all columns composing the PRIMARY KEY (the IN relation is only
supported for the last column of the partition key). Other columns
values are specified through after the SET keyword.
The description in the specification of the DELETE statement begins with a similar paragraph:
The DELETE statement deletes columns and rows. If column names are provided
directly after the DELETE keyword, only those columns are deleted from the row
indicated by the (where-clause) (the id[value] syntax in (selection) is for
collection, please refer to the collection section for more details).
Otherwise whole rows are removed. The (where-clause) allows to specify the
key for the row(s) to delete (the IN relation is only supported for the last
column of the partition key).
The bolded portions of each of these descriptions state, in layman's terms, that these statements can be used to modify data in a solely row-based manner.
However, given the nature of the relationship (or lack thereof) between the rows and the static columns (which exist independent of any particular row) of a table, it seems as though there should be a way to modify such columns given only the keys of the partitions they're respectively contained in. According to the specification however, that does not seem to be possible, and I'm not sure if that is a product of the difficulty to allow such in the CQL3 syntax, or something else.
If a static column cannot be updated or deleted independent of any row in its table, then such operations become coupled with their non-static-column-based counterparts, making the set of columns targeted by such operations, difficult to determine. For example, given a populated table with the following definition:
CREATE TABLE IF NOT EXISTS example_table
(
partitionKeyColumn int
clusteringColumn int
nonPrimaryKeyColumn int
staticColumn varchar static
PRIMARY KEY (partitionKeyColumn, clusteringColumn)
)
... it is not immediately obvious if the following DELETE statements are equivalent:
//#1 (Explicitly specifies all of the columns in and "in" the target row)
DELETE partitionKeyColumn, clusteringColumn, nonPrimaryKeyColumn, staticColumn FROM example_table WHERE partitionKeyColumn = 1 AND clusteringColumn = 2
//#2 (Implicitly specifies all of the columns in (but not "in"?) the target row)
DELETE FROM example_table WHERE partitionKeyColumn = 1 AND clusteringColumn = 2
So, phrasing my observations in question form:
Are the above DELETE statements equivalent?
Does the primary key of at least one row in a CQL3 table have to be supplied in order to update or delete a static column in said table? If so, why?
I do not know about specification but in the real cassandra world, your two DELETE statements are not equivalent.
The first statement deletes the static_column whereas the second one does not. The reason of this is that static columns are shared by rows. You have to specify it explicitly to actually delete it.
Furthermore, I do not think its a good idea to DELETE static columns and non-static columns at the same time. By the way, this statement won't work :
DELETE staticColumn FROM example_table WHERE partitionKeyColumn = 1 AND clusteringColumn = 2
The error output is :
Bad Request: Invalid restriction on clustering column priceable_name since the DELETE statement modifies only static columns
I have an existing sybase ase table which is using IDENTITY as its primary key. Now i need to recreate this table but i want to start the PK from next value of IDENTITY PK in prod env. e.g. If currently PK = 231 then after re-creating i want it to start from 232 onwards or any other INTEGER value > 231.
In oracle its easy to configure a sequence number and we can give start with but in sybase ase as we dont have sequence available so i tried using newid() function but it gives binary(16) values whereas i want integer values.
Can anyone suggest something ?
I am planning to use something like mentioned below and i think it will resolve my problem. Let me know if anyone has a better solution.
select abs(hextoint(newid()))
Any thoughts on this solution ? Can this ever generate the same number which it generated already?
select next_identity('tablename') will return the identity value of the next insert for a table with an identity column so you know which ID will be allocated next.
Select ##identity immediately after an insert will return the ID which was just given to the row inserted.
However you need to be careful as identity columns are not the same as sequences and should not be relied upon if you want a sequence with no gaps because you will get a gap (albeit small sometimes) if the database crashes or is shutdown with nowait. For these a number fountain/insert trigger type generation of IDs is a better option. Using 'identity insert' is only really for when you want to bulk-load a whole table - you should not be setting that with every insert or you will defeat the whole purpose of an identity column, which is fast generation of new key values.