⟩ Explain OPENQUERY function and OPENROWSET function?
OPENQUERY: - Used to execute the query passed on the linked server.
Syntax: OPENQUERY (Linked_server_identifier, query). It can also be refernced from a FROM clause of selecte query.
e.g. Select * from OPENQUERY (Oracleserver, ‘select fname, FROM Employee);
OPENROWSET: - Used to access tables in a linked server. It can be used one time for accessing remote data by using OLE DB. It includes all the information required to access the remote data.
Syntax:
OPENROWSET
( { 'provider_name' , { 'datasource' ; 'user_id' ; 'password'
| 'provider_string' }
, { [ catalog. ] [ schema. ] object
| 'query'
}
| BULK 'data_file' ,
{ FORMATFILE = 'format_file_path' [ ]
| SINGLE_BLOB | SINGLE_CLOB | SINGLE_NCLOB }
} )