Concat variable with a string in location parameter in a create statement? - ddl

Question

In Greenplum, I need to create an external table with a dynamic location parameter. For an example:
CREATE READABLE TABLE_A(
date_inic date,
func_name varchar,
q_session bigint
)
LOCATION(:location)
FORMAT 'TEXT' (DELIMITER '|');
But in :location parameter I need to concat it with a fixed string. I tried:
LOCATION (:location || '123')
But I get a syntax error, otherwise in select statement it works perfectly. I'm inserting :location value like: " 'gphdfs://teste:1010/tmp' "
Can anyone help me?

Answer 1

You are missing a few things in your table definition. You forgot "external" and "table".
CREATE READABLE EXTERNAL TABLE table_a
(
date_inic date,
func_name varchar,
q_session bigint
)
LOCATION(:location)
FORMAT 'TEXT' (DELIMITER '|');
Note: gphdfs has been deprecated and you should use PXF or gpfdist instead.
Next, you just need to use double quotes around the location value.
[gpadmin#mdw ~]$ psql -f example.sql -v location="'gpfdist://teste:1010/tmp'"
CREATE EXTERNAL TABLE
[gpadmin#mdw ~]$ psql
psql (9.4.24)
Type "help" for help.
gpadmin=# \d+ table_a
External table "public.table_a"
Column | Type | Modifiers | Storage | Stats target | Description
-----------+-------------------+-----------+----------+--------------+-------------
date_inic | date | | plain | |
func_name | character varying | | extended | |
q_session | bigint | | plain | |
Type: readable
Encoding: UTF8
Format type: text
Format options: delimiter '|' null '\N' escape '\'
External options: {}
External location: gpfdist://teste:1010/tmp
Execute on: all segments
And from bash, you can just concat the strings together too.
loc="gpfdist://teste"
port="1010"
dir="tmp"
location="'""$loc"":""$port""/""$dir""'"
psql -f example.sql -v location="$location"