Generic API call

Calls an Elasticsearch API when no dedicated endpoint is defined. Use generic_request with Url, RequestMethod, and optional Body or Headers. The example shows a CREATE INDEX-style PUT request.

Standard SQL query example

This is the base query accepted by the connector. To execute it in SQL Server, you have to pass it to the Data Gateway via a Linked Server. See how to accomplish this using the examples below.

SELECT * FROM generic_request 
WITH(Url='/my_index_name'
	, RequestMethod='PUT'
--	, Body='{}'
--	, Headers='X-Hdr1:aaa || x-HDR2: bbb'
	, Meta='acknowledged:bool'
	)

Using OPENQUERY in SQL Server

SELECT * FROM OPENQUERY([LS_TO_ELASTICSEARCH_IN_GATEWAY], 'SELECT * FROM generic_request 
WITH(Url=''/my_index_name''
	, RequestMethod=''PUT''
--	, Body=''{}''
--	, Headers=''X-Hdr1:aaa || x-HDR2: bbb''
	, Meta=''acknowledged:bool''
	)')

Using EXEC in SQL Server (handling larger SQL text)

The major drawback of OPENQUERY is its inability to incorporate variables within SQL statements. This often leads to the use of cumbersome dynamic SQL (with numerous ticks and escape characters).

Fortunately, starting with SQL 2005 and onwards, you can utilize the EXEC (your_sql) AT [LS_TO_ELASTICSEARCH_IN_GATEWAY] syntax.

DECLARE @MyQuery NVARCHAR(MAX) = 'SELECT * FROM generic_request 
WITH(Url=''/my_index_name''
	, RequestMethod=''PUT''
--	, Body=''{}''
--	, Headers=''X-Hdr1:aaa || x-HDR2: bbb''
	, Meta=''acknowledged:bool''
	)'
EXEC (@MyQuery) AT [LS_TO_ELASTICSEARCH_IN_GATEWAY]