CoreData - SQLite の LIMIT

-[NSFetchRequest setFetchBatchSize:] で指定したサイズ値がフェッチ時に発行される SQLの LIMIT値となる。

例えば

[fetchRequest setFetchBatchSize:20];

とするとSQLはこうなる。

SELECT 0, t0.Z_PK, t0.Z_OPT, t0.ZMODIFIEDDATE, t0.ZFEE, t0.ZMEMO, t0.ZCREATEDDATE, t0.ZOPERATEDDATE, t0.ZCUSTOMER FROM ZKARTE t0 WHERE  t0.Z_PK IN  (?,?,?)  ORDER BY t0.ZOPERATEDDATE DESC LIMIT 20

３件ヒットするケースで、サイズを1とすると

[fetchRequest setFetchBatchSize:1];

こうなる。

sql: SELECT 0, t0.Z_PK, t0.Z_OPT, t0.ZMODIFIEDDATE, t0.ZFEE, t0.ZMEMO, t0.ZCREATEDDATE, t0.ZOPERATEDDATE, t0.ZCUSTOMER FROM ZKARTE t0 WHERE  t0.Z_PK IN  (?)  ORDER BY t0.ZOPERATEDDATE DESC LIMIT 1

sql: SELECT 0, t0.Z_PK, t0.Z_OPT, t0.ZMODIFIEDDATE, t0.ZFEE, t0.ZMEMO, t0.ZCREATEDDATE, t0.ZOPERATEDDATE, t0.ZCUSTOMER FROM ZKARTE t0 WHERE  t0.Z_PK IN  (?)  ORDER BY t0.ZOPERATEDDATE DESC LIMIT 1

sql: SELECT 0, t0.Z_PK, t0.Z_OPT, t0.ZMODIFIEDDATE, t0.ZFEE, t0.ZMEMO, t0.ZCREATEDDATE, t0.ZOPERATEDDATE, t0.ZCUSTOMER FROM ZKARTE t0 WHERE  t0.Z_PK IN  (?)  ORDER BY t0.ZOPERATEDDATE DESC LIMIT 1

LIMIT 1 のSQLが件数分（３件）発行される。

※iPhone OS 3.1.3 用コードで確認