ODBC SQL import best practices

[mjohnsonuk]

Hi All,

I was wondering what is the best prctice for ODBC queries

I am looking to query two large tables one contains an active status and one doesnt ....

If I go to Get data > ODBC > Advanced and type in the SQL below to join the two tables is this the best way or is it best to query both tables seperatly and edit / merge them in power BI before running the close and load ???

than kyou in advance

SELECT
a.cust_code,
a.date_created,
a.guarantee_end_date,
a.inv_status_code,
a.invn_code,
a.model,
a.num,
a.prem_code,
a.status_ind,
a.styp_code,
b.cust_code_owner,
b.code,
b.zipc_code,
b.post_in_code,
b.postcode_sector_id
FROM database1.customer a
LEFT OUTER JOIN database1.premise b
ON a.cust_code = b.cust_code_owner
AND a.prem_code = b.code
WHERE a.status_ind ="A"
AND a.styp_code = "ABA"
OR a.styp_code = "ABB"
OR a.styp_code = "ABC";

[Anonymous]

@mjohnsonuk, 

From my experience, it is better to write your own custom SQL. You could do the latter but sometimes ODBC does not perform query folding correctly, hence it will perform the join in your local memory instead of at the server.