Jeg får fejlen i følgende forespørgsel:
SELECT DISTINCT UNIQUE_ID as uid, CONFIDENCE_IS_SAME FROM ( (SELECT UNIQUE_ID, CONFIDENCE_IS_SAME, FIRST_NAME, LAST_NAME, POSTAL_CODE FROM DANIEL.UNIQUE_PHYSICIAN WHERE DANIEL.UNIQUE_PHYSICIAN.FIRST_NAME = "" AND DANIEL.UNIQUE_PHYSICIAN.LAST_NAME = "" AND DANIEL.UNIQUE_PHYSICIAN.IS_ROOT_PHYS = 0 AND DANIEL.UNIQUE_PHYSICIAN.POSTAL_CODE = "") INNER JOIN (SELECT MAX(CONFIDENCE_IS_SAME) OVER (PARTITION BY ROOT_ID) max_conf FROM DANIEL.UNIQUE_PHYSICIAN WHERE DANIEL.UNIQUE_PHYSICIAN.FIRST_NAME = "" AND DANIEL.UNIQUE_PHYSICIAN.LAST_NAME = "" AND DANIEL.UNIQUE_PHYSICIAN.IS_ROOT_PHYS = 0 AND DANIEL.UNIQUE_PHYSICIAN.POSTAL_CODE = "") ON CONFIDENCE_IS_SAME = max_conf); Svar
Du har brug for et alias for begge afledte tabeller. Og det ydre par omkring from klausul er ubrugelig.
SELECT DISTINCT t1.unique_id AS uid, t1.confidence_is_same FROM ( --<< only one opening parenthesis SELECT unique_id, confidence_is_same, first_name, last_name, postal_code FROM daniel.unique_physician WHERE daniel.unique_physician.first_name = "" AND daniel.unique_physician.last_name = "" AND daniel.unique_physician.is_root_phys = 0 AND daniel.unique_physician.postal_code = "" ) t1 ---<< the alias for the derived table is missing INNER JOIN ( SELECT max(confidence_is_same) OVER (PARTITION BY root_id) max_conf FROM daniel.unique_physician WHERE daniel.unique_physician.first_name = "" AND daniel.unique_physician.last_name = "" AND daniel.unique_physician.is_root_phys = 0 AND daniel.unique_physician.postal_code = "" ) t2 ON t1.confidence_is_same = t2.max_conf Men sammenføjningen er ikke nødvendig i første omgang. Din forespørgsel kan forenkles til:
SELECT DISTINCT t1.unique_id AS uid, t1.confidence_is_same FROM ( SELECT unique_id, confidence_is_same, max(confidence_is_same) OVER (PARTITION BY root_id) max_conf FROM daniel.unique_physician unq WHERE unq.first_name = "" AND unq.last_name = "" AND unq.is_root_phys = 0 AND unq.postal_code = "" ) t1 where confidence_is_same = max_conf; Du behøver ikke at vælge first_name, last_name og postal_code i det indre valg, da du ikke bruger dem i det ydre valg. Dette kan gøre forespørgslen potentielt mere effektiv.
Derudover vil betingelsen unq.last_name = "" ikke gøre, hvad du tror, den gør. Oracle har ikke en “tom streng” “. En streng med længden nul ("") gemmes som NULL, så det, du virkelig vil have, er sandsynligvis:
SELECT DISTINCT t1.unique_id AS uid, t1.confidence_is_same FROM ( SELECT unique_id, confidence_is_same, max(confidence_is_same) OVER (PARTITION BY root_id) max_conf FROM daniel.unique_physician unq WHERE unq.first_name is null AND unq.last_name is null AND unq.is_root_phys = 0 AND unq.postal_code is null ) t1 where confidence_is_same = max_conf;