Oracle PHP Cookbook: Working with Dates and Times in Oracle and PHP

Oracle PHP Cookbook: Working with Dates and Times in Oracle and PHP:

To convert a UNIX timestamp into an Oracle DATE type:

CREATE OR REPLACE
   FUNCTION unixts_to_date(unixts IN PLS_INTEGER) RETURN DATE IS
       /**
        * Converts a UNIX timestamp into an Oracle DATE
        */
       unix_epoch DATE := TO_DATE('19700101000000','YYYYMMDDHH24MISS');
       max_ts PLS_INTEGER := 2145916799; -- 2938-12-31 23:59:59
       min_ts PLS_INTEGER := -2114380800; -- 1903-01-01 00:00:00
       oracle_date DATE;
      
       BEGIN
          
           IF unixts > max_ts THEN
               RAISE_APPLICATION_ERROR(
                   -20901,
                   'UNIX timestamp too large for 32 bit limit'
               );
           ELSIF unixts < min_ts THEN
               RAISE_APPLICATION_ERROR(
                   -20901,
                   'UNIX timestamp too small for 32 bit limit' );
           ELSE
               oracle_date := unix_epoch + NUMTODSINTERVAL(unixts, 'SECOND');
           END IF;
          
           RETURN (oracle_date);
      
   END;