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/
Related
It's been a while.
Using DB2 10 for z/OS, I've been asked to change a specific column in a table from decimal(7,2) to decimal(7,4). Sounds easy, right?
alter table MySchema.MyTable
alter column myColumn
set data type decimal(7,4);
But, DB2 responds with this error: "Attributes specified for column 'MYCOLUMN' are incompatible with existing column definition."
I had thought that converting from decimal(7,2) to decimal(7,4) would be pretty straightforward, but DB2 disagrees.
Outside of dropping the table and recreating it from scratch, what alternatives do I have?
Thanks in advance!
Dave
The reason Db2 doesn't like that change is you're going from from 99999.99 to 999.9999
Is that really what you want? Going from (7,2) to (9,4) would just add two more decimal places without losing any data and should be allowed by the Db.
Db2 for i gives a warning, but allows you to ignore the warning...
Create a new column ALTER ADD COLUMN of the right type, use an UPDATE to populate it, ALTER DROP COLUMN the old column. RENAME COLUMN so set the name of the original column.
I have a CSV file file.csv.
In Postgres, I have made a table named grants:
CREATE TABLE grants
(
)
WITH (
OIDS=FALSE
);
ALTER TABLE grants
OWNER TO postgres;
I want to import file.csv data without having to specify columns in Postgres.
But if I run COPY grants FROM '/PATH/TO/grants.csv' CSV HEADER;, I get this error: ERROR: extra data after last expected column.
How do I import the CSV data without having to specify columns and types?
The error is normal.
You created a table with no column. The COPY command try to import data into the table with the good structure.
So you have to create the table corresponding to your csv file before execute the COPY command.
I discovered pgfutter :
"Import CSV and JSON into PostgreSQL the easy way. This small tool abstract all the hassles and swearing you normally have to deal with when you just want to dump some data into the database"
Perhaps a solution ...
The best method for me was to convert the csv to dataframe and then follow
https://github.com/sp-anna-jones/data_science/wiki/Importing-pandas-dataframe-to-postgres
No, it is not possible using the COPY command
If a list of columns is specified, COPY will only copy the data in the
specified columns to or from the file. If there are any columns in the
table that are not in the column list, COPY FROM will insert the
default values for those columns.
COPY does not create columns for you.
I'm trying to import a CSV file with column names "Zip Code", "2010 Population", "Land-Sq-Mi" and "Density per Sq Mile" into my test table, which is named derp--that's why I have the drop statement at the beginning, so I don't replicate any rows and can start clean in each iteration.
Code is as follows:
DROP TABLE derp;
CREATE TABLE public.derp("Zip Code" varchar, "2010 Population" integer, "Land-Sq-Mi" numeric, "Density Per Sq Mile" numeric);
COPY derp("Zip Code", "2010 Population", "Land-Sq-Mi", "Density Per Sq Mile")
FROM '/home/michael/PycharmProjects/cmsDataProject/Zipcode-ZCTA-Population-Density-And-Area-Unsorted.csv'
DELIMITER','
CSV HEADER;
This does a fine job of importing the actual data, but it leaves the column headers blank in the pgadmin III data view. I looked at the source file in Nano--the headers are there, and if they weren't the query would have thrown a syntax error telling me that there was no relation for the column I was trying to import into.
Any ideas about what I'm doing wrong?
Edit: I would like pgadmin III data view to display the header names, and possibly a way to verify that the columns are actually named even if they aren't being imported and not displayed. To reiterate, every row after the headers is intact and in view, just the header row is blank.
Edit 2: When I CREATE TABLE public.derp(); and then manually add the columns, they show correctly in the data view. Something about the multi-line query statement was causing the breakage.
So pgadmin is not showing the column names but it's showing the data?
If you open a table in pgadmin, then alter the table, but keep the table window open, it seems to lose the column names.
Close the window with the table. Click the tables icon in the pgadmin tree view and refresh the tables, and reopen the table window.
I'm using PostgreSQL database, after I've created my table I have to populate them with a CSV file. However the CSV file is corrupted and it violates the primary key rule and so the database is throwing an error and I'm unable to populate the table. Any ideas how to tell the database to ignore the duplicates when importing from CSV? Writing a script to remove them from the CSV file is no acceptable. Any workarounds are welcome too. Thank you! : )
On postgreSQL, duplicate rows are not permitted if they violate a unique constraint.
I think that your best option, is to import your CSV file on to temp table that has no constraint, delete from it duplicate values, and finally import from this temp table to your final table.
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 .. )