I'm trying to create a HIVE query
from an Oracle SQL query
. Essentially I want to select the first record, sorted descending
by UPDATED_TM, DATETIME, ID_NUM
.
SELECT
tbl1.NUM AS ID,
tbl1.UNIT AS UNIT,
tbl2.VALUE AS VALUE,
tbl1.CONTACT AS CONTACT_NAME,
'FILE' AS SOURCE,
CURDATE() AS DATE
FROM
DB1.TBL1 tbl1
LEFT JOIN DB1.TBL2 tbl2 ON tbl1.USR_ID = tbl2.USR_ID
WHERE
tbl1.UNIT IS NOT NULL
AND tbl1.TYPE = 'Generic'
QUALIFY
ROW_NUMBER() OVER (PARTITION BY tbl1.ROW_ID ORDER BY tbl1.UPDATED_TM DESC, tbl1.DATETIME DESC, tbl1.ID_NUM DESC) = 1
And my attempt at an equivalent Hive query
(but also sql-compatible):
SELECT
tbl1.NUM AS ID,
tbl1.UNIT AS UNIT,
tbl2.VALUE AS VALUE,
tbl1.CONTACT AS CONTACT_NAME,
'FILE' AS SOURCE,
CURDATE() AS DATE
FROM (
SELECT
USR_ID, TYPE, NUM, UNIT, ROW_NUMBER() OVER (PARTITION BY tbl1.ROW_ID ORDER BY tbl1.UPDATED_TM DESC, tbl1.DATETIME DESC, tbl1.ID_NUM DESC) AS RNUM
FROM
DB1.TBL1
) tbl1
LEFT JOIN DB1.TBL2 tbl2 ON tbl1.USR_ID = tbl2.USR_ID
WHERE
tbl1.RNUM = 1
AND tbl1.UNIT IS NOT NULL
AND tbl1.TYPE = 'Generic'
Does that seem correct? Is there any way I can optimize the query? The tables I'm working with are quite large and I would like to make this as efficient as possible.
Thanks.
SELECT
tbl1.NUM AS ID,
tbl1.UNIT AS UNIT,
tbl2.VALUE AS VALUE,
tbl1.CONTACT AS CONTACT_NAME,
'FILE' AS SOURCE,
CURDATE() AS DATE
FROM
(
SELECT
USR_ID, TYPE, NUM, UNIT, ROW_NUMBER() OVER (PARTITION BY tbl.ROW_ID ORDER BY tbl.UPDATED_TM DESC, tbl.DATETIME DESC, tbl.ID_NUM DESC) AS RNUM
FROM
(
SELECT
USR_ID,TYPE,NUM,UNIT,ROW_ID,UPDATED_TM,DATETIME,ID_NUM
FROM DB1.TBL1
WHERE UNIT IS NOT NULL
AND TYPE = 'Generic'
)tbl
)tbl1
LEFT OUTER JOIN
DB1.TBL2 tbl2
ON tbl1.USR_ID = tbl2.USR_ID
WHERE tbl1.RNUM = 1;