TIMESTAMP अंतर कॉलम डेटा को स्ट्रिंग प्रारूप में कनवर्ट करें

with t as (
  select 1 as msg_guid,
    interval '0 0:0:0.343009' day to second as diff
  from dual
)
select trunc(extract (second from diff) * 1000)
from t;

TRUNC(EXTRACT(SECONDFROMDIFF)*1000)
-----------------------------------
                                343 

यहां आपकी असली क्वेरी उस डमी सीटीई की जगह लेगी जिसका मैंने इंटरवल लिटरल के साथ इस्तेमाल किया था।

यदि अंतराल एक सेकंड से अधिक हो सकता है, तो आप संभवतः पूरे मान को मिलीसेकंड में प्राप्त करना चाहते हैं, इसलिए आपको सभी तत्वों को निकालने और उन्हें एक साथ जोड़ने की आवश्यकता होगी, प्रत्येक को उनके प्रतिनिधित्व के आधार पर गुणा करना होगा - इसलिए एक पूरा दिन होगा 86400000 मिलीसेकंड आदि हो; सादे तत्व इस तरह निकलेंगे:

column diff format a25
with t as (
  select 1 as msg_guid,
    systimestamp - trunc(systimestamp) as diff
  from dual
)
select diff,
  extract (day from diff) as dd,
  extract (hour from diff) as hh,
  extract (minute from diff) as mi,
  extract (second from diff) as ss
from t;

DIFF                           DD         HH         MI         SS
---------------------- ---------- ---------- ---------- ----------
0 9:13:26.150627                0          9         13  26.150627 

और आप उन्हें इस तरह संयोजित करेंगे:

with t as (
  select 1 as msg_guid,
    systimestamp - trunc(systimestamp) as diff
  from dual
)
select diff,
  trunc(1000 * (
    extract (day from diff) * (60*60*24)
    + extract (hour from diff) * (60*60)
    + extract (minute from diff) * 60
    + extract (second from diff)
  )) as milliseconds
from t;

DIFF                   MILLISECONDS
---------------------- ------------
0 9:13:27.650365           33207650 

लेकिन आपके पिछले प्रश्न के आधार पर, शायद आप इसे अलग-अलग घटकों के रूप में एक स्ट्रिंग के रूप में चाहते हैं:

with t as (
  select 1 as msg_guid,
    systimestamp - trunc(systimestamp) as diff
  from dual
)
select diff,
  extract (day from diff) || ' DAYS '
    || extract (hour from diff) || ' HOURS '
    || extract (minute from diff) || ' MINUTES '
    || trunc(extract (second from diff)) || ' SECONDS '
    || (trunc(extract (second from diff) * 1000)
      - (trunc(extract (second from diff)) * 1000)) || ' MILLISECONDS'
    as text
from t;

DIFF                   TEXT                                                   
---------------------- -------------------------------------------------------
0 9:43:38.896007       0 DAYS 9 HOURS 43 MINUTES 38 SECONDS 896 MILLISECONDS

SQL Fiddle आपके नमूना डेटा के आधार पर, प्रकार, और समय की गणना के उलट होने के कारण मान सकारात्मक है।