URL-based Web External Tables
A URL-based web table accesses data from a web server using the HTTP protocol. Web table data is dynamic; the data is not rescannable.
Specify the LOCATION
of files on a web server using http://
. The web data file(s) must reside on a web server that HAWQ segment hosts can access. The number of URLs specified corresponds to the minimum number of virtual segments that work in parallel to access the web table.
The following sample command defines a web table that gets data from several URLs.
=# CREATE EXTERNAL WEB TABLE ext_expenses (
name text, date date, amount float4, category text, description text)
LOCATION ('http://intranet.company.com/expenses/sales/file.csv',
'http://intranet.company.com/expenses/exec/file.csv',
'http://intranet.company.com/expenses/finance/file.csv',
'http://intranet.company.com/expenses/ops/file.csv',
'http://intranet.company.com/expenses/marketing/file.csv',
'http://intranet.company.com/expenses/eng/file.csv'
)
FORMAT 'CSV' ( HEADER );