SQL & PL/SQL

Hi! I got a table:

CREATE TABLE SampleTable (

  A_ID                    NUMBER             NOT NULL,

  A_COL_VAL               VARCHAR2(128 BYTE),

  TABLE_INSERT_TIME       TIMESTAMP(2)       DEFAULT SYS_EXTRACT_UTC(SYSTIMESTAMP),

)

TABLESPACE USERS

STORAGE (INITIAL 64 K

         NEXT 1 M

         MAXEXTENTS UNLIMITED)

LOGGING;

Need to get the last N records for the last X days.

What's the most efficient query I can write? The table

has over 2 mln records and I cannot change the design.

• If there are more than N records in the last X days, only N should be retrieved.
• If there are fewer records than N in the last X days, all records should be retrieved.

Is subquery the way to go? Rank?

MAX_CNT NUMBER := 5000;

LAST_NUM_DAYS NUMBER:= 150;

Infinite thanks in advance,