Export specific query data to CSV file from netezza database

Question

I wanted to export data from netezza database to CSV file.

The format for the data will be:

col1,col2,col3

OR:

"col1","col2","col3"

I am using the query:

CREATE EXTERNAL TABLE 'H:\\test.csv' USING ( DELIMITER ',' REMOTESOURCE 'ODBC' ) AS
SELECT * FROM TEST_TABLE

Above query is not working when col3 has the field including comma as it is saying to export it using escape char as '\'.

Example table:

A | B | C
a | b | Germany, NA

I tried that too, but I am getting as output in csv:

a,b,Germany\, NA

or by adding quotes to each column I am getting output:

"a","b","Germany\, NA"  

Here, I am getting extra '\' character in field. I am looking for the solution to resolve it using the nzsql or external table query method or writing own script methods only.

My expected output without changing field data:

"a","b","Germany, NA"

Answer 1

Desired output can be achieved by using nzsql command line statement.The only limitation of this approach is max file will limit to 2 GB .Here is the link from IBM KB Sending query results to an output file

[nz@netezza ~]$ nzsql -d test -A -t -c  "select quote_ident(col1),quote_ident(col2), quote_ident(col3) from test" -o '/nzscratch/test.csv'

Output :

[nz@netezza ~]$ cat /nzscratch/test.csv
"A"|"B"|"C"
a|b|"Germany, NA"

Answer 2

You can use ESCAPECHAR '@' to use an '@' rather than a backslash only a backlash as an escape character. The problem is that a csv file needs a way to say "this comma is data, not a delimiter" - which is what the escape char is used for. The code that consumes your csv file should be configured to expect that same escape character.

This is one of the quirks you run into when using a loosely defined data format like csv. As long as you define a delimiter and an escape character that the producer and consumer both expect - and you're using the same character encoding - you'll be fine.

This isn't changing your data, it's just making the interchange format more specific. If you provide some detail on what is consuming the data, I can update this answer to provide detail on informing the consumer that backslashes are used as an escape character.

-- EDIT -- Apparently some implementations of netezza only support backslash as a delimiter.

IBM References:

• QuotedValue
• EscapeChar
• Delimiter