I wanted to prepare a load utility to load the data into DB2 table. The table has columns which contains GENERATEDALWAYS feature set.
So, I am not able to load an unloaded details from the table.
Is it possible to use import for tables having columns with GENERATEDALWAYS set?
Steps I did:
1. db2 "export to tbl.txt of del modified by coldel| select * from <schema.table> where col=value"
2. db2 "delete from <schema.table> where col=value"
3. db2 "import from tbl.txt of del modified by coldel| allow write access warningcount1 insert into <schema.table>"
The columns with "GENERATEDALWAYS" is having NEW Value after import. Is it possible to use import to populate GENERATEDALWAYS columns to have the old values?
Appreciate the assistance.
Thanks,
Mathew Liju
What you are asking is not possible. With IMPORT you can't override columns that have GENERATED ALWAYS. As #Peter Miehle suggests you could alter the table to specify that the column is GENERATED BY DEFAULT, but this may break other applications.
Your question's title implies that you don't want to use the LOAD utility (but you don't mention anything about it in the actual question). However, LOAD is the only way to write data into the table and maintain the values for the generated column as they exist in the file:
db2 "load from tbl.txt of del modified by generatedoverride insert into schema.table"
If you do this, be aware that:
DB2 does not check if there are conflicts with existing rows in the table. You would need to define a unique index on the column(s) in question to resolve this; this would cause DB2 to delete the rows that you just loaded in the DELETE phase of the load.
If your generated column(s) are using IDENTITY, make sure that you alter the column to ensure that future generated values do not conflict with the rows that you just inserted into the table.
maybe you can drop the "generation" from the column and add it after importing with the appropriate values again.
#Ian Bjorhovde has given you the options.
IMPORT actually does INSERTs in the background - ie, it first prepares a INSERT statement with parameter markers and uses the values in the input file for those markers.
In your SQL snapshot you will see INSERT statement that is used.
Anything that is not possible in an INSERT statement isn't possible with IMPORT (kind of .. )
Related
I am working with a table that has many constraints.
I am receiving errors while importing a clean data in the table.
I want to know at what time these constraints were added to the table so that I can have an idea whether it was after or before the bulk import in that table.
How can I find out when a constraint was added to a table (the date of creation of constraint)
I use PostgreSQL 10
PostgreSQL doesn't record this information in the metadata.
If you have log_statement = 'ddl', you might find the information in the log file.
I am using PostgreSQL 9.6. I have created a table with create query.
But when i checked in left panel of pgAdmin, under table i found more six columns named tableid,cmax,xmax,cmin,xmin and ctid.
When i searched about this, I found that these are OIDs column and does not affect to data on other columns.
I have to import data into this table. So after selecting table, from right click i got option for import/Export. So from that i am importing .csv file.
But when i tried to import the data in table, i am getting error like,
ERROR: column "tableoid" of relation "account" does not exist
Please suggest me how to eliminate these OID columns from table.
You must be missing some column that is present in the csv named "tableoid".
In this case ,TABLE according to the import file must be created first. IF there is no prior table , it wont work. This may help.
http://www.postgresqltutorial.com/import-csv-file-into-posgresql-table/
I'm using DataGrip 2016.3 to connect to a PostgreSQL server.
When I right click and Import From File, currently DataGrip makes assumptions about the type associated with each column
(see image for what DataGrip defaults to in the import dialog). I'd like to specify that column A is VARCHAR(50), column B is INT, column C is DATE, and so on. I will be uploading similar files multiple times, and I'd like to avoid having to specify my types each time I import. Is there a way to save and select configurations of columns A, B, and C's types?
The best way that I've found to accomplish this is to first create the destination table. Then Right-click on the table in the database tool window to launch the "Import Data from File..." wizard.
This is also great if you want the destination table to contain additional columns, such as an auto-incrementing id column.
I am trying to rename a table in db2 like so
rename table schema1.mytable to schema2.mytable
but getting the following error message:
the name "mytable" has the wrong number of qualifiers.. SQLCODE=-108,SQLSTATE=42601
what is the problem here.... I am using the exact syntax from IBM publib documentation.
You cannot change the schema of a given object. You have to recreate it.
There are severals ways to do that:
If you have only one table, you can export and import/load the table. If you use the IDX format, the DDL will be included in the generated file. If using another format, the table has be created.
You can recreate the table by using:
Create table schema2.mytable like schema1.mytable
You can extract the DDL with the db2look tool
If you are changing the schema name for a schema given, you can use ADMIN_COPY_SCHEMA
These last two options only create the table structure, and you still need to import the data. After having create the table, you insert the data by different ways:
Inserting directly
insert into schema2.mytable select * from schema1.mytable
Via load from cursor
Via a Load or import from file (The file exported in the previous step)
The problem is the foreign relations, because they have to be recreated.
Finally, you can create an alias. It is easier, and you do not have to deal with relations.
You can easily rename a table with this statement:
RENAME TABLE SCHEMA.TABLENAME TO NEWTABLENAME;
You're not renaming table in provided example, you're trying to move to different schema, it's not the same thing. Look into db2move tool for this.
if you want to rename a table in the same schema, you can use like this.
RENAME TABLE schema.table_name TO "new_table_name";
Otherwise, you can use tools like DBeaver to rename or copy tables in a db2 db.
What if you leave it as is and create an alias with the new name and schema.
Renaming a table means to rename a table within same schema .To rename in other schema ,db2 call its ALIAS:
db2 create alias for
I'm working on an application that imports data from Access to SQL Server 2008. Currently, I'm using a stored procedure to import the data individually by record. I can't go with a bulk insert or anything like that because the data is inserted into two related tables...I have a bunch of fields that go into the Account table (first name, last name, etc.) and three fields that will each have a record in an Insurance table, linked back to the Account table by the auto-incrementing AccountID that's selected with SCOPE_IDENTITY in the stored procedure.
Performance isn't very good due to the number of round trips to the database from the application. For this and some other reasons I'm planning to instead use a staging table and import the data from there. Reading up on my options for approaching this, a cursor that executes the same insert stored procedure on the data in the staging table would make sense. However it appears that cursors are evil incarnate and should be avoided.
Is there any way to insert data into one table, retrieve the auto-generated IDs, then insert data for the same records into another table using the corresponding ID, in a set-based operation? Or is a cursor my only option here?
Look at the OUTPUT clause. You should be able to add it to your INSERT statement to do what you want.
BTW, if you need to output columns into the second table that weren't inserted into the first one, then use MERGE instead of INSERT (as suggested in the comment to the original question) as its OUTPUT clause supports referencing other columns from the source table(s). Otherwise, keeping it with an INSERT is more straightforward, and it does give you access to the inserted identity column.
I'm having experiment to worked out in inserting multiple record into related table using databinding. So, try this!
Hopefully this is very helpful. Follow this link How to insert record into related tables. for more information.