Konverter TIMESTAMP difference kolonnedata til strengformat

Når du tilføjer eller trækker tidsstempler fra, er resultatet et interval , ikke et andet tidsstempel. Du kan bruge extract funktion at trække komponenterne ud af det. Hvis din værdi altid vil være sub-sekund, kan du bare udtrække sekunderne og gange med tusind for at få millisekunderne:

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 

Her ville din rigtige forespørgsel træde i stedet for den dummy CTE, jeg brugte med et interval literal.

Hvis intervallet kan være mere end et sekund, vil du formentlig ønske at få hele værdien i millisekunder, så du bliver nødt til at udtrække alle elementerne og lægge dem sammen, multiplicere hver baseret på, hvad de repræsenterer - så en hel dag ville være 86400000 millisekunder osv.; de almindelige elementer ville komme ud som:

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 

Og du ville kombinere dem som:

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 

Men baseret på dit tidligere spørgsmål, vil du måske have det som en streng, som de separate komponenter:

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 baseret på dine prøvedata, slags og med tidsberegningen omvendt, så værdien er positiv.