Using the WRITETIME function in a SELECT statement to determine when the date/time
that the column was written to the database.
A table contains a timestamp representing the date/time that a write occurred to a
column. Using the WRITETIME function in a SELECT statement returns the date/time
that the column was written to the database. The output of the function is
microseconds except in the case of Apache Cassandra™ 2.1 counter columns. Counter column
writetime is milliseconds. This procedure continues the example from the previous
procedure and calls the WRITETIME function to retrieve the date/time of the writes
to the columns.
Procedure
-
Insert more data into the table.
INSERT INTO excelsior.clicks (
userid, url, date, name)
VALUES (
cfd66ccc-d857-4e90-b1e5-df98a3d40cd6,
'http://google.com',
'2013-10-11', 'Bob'
);
-
Retrieve the date/time that the value Mary was written to the name column of
the apache.org data. Use the WRITETIME function in a SELECT statement, followed
by the name of a column in parentheses:
SELECT WRITETIME (name) FROM excelsior.clicks
WHERE url = 'http://apache.org' ALLOW FILTERING;
The writetime output in microseconds converts to Sun, 14 Jul 2013
21:57:58 GMT or to 2:57 pm Pacific time.
writetime(name)
------------------
1373839078327001
-
Retrieve the date/time of the last write to the date column for google.com
data.
SELECT WRITETIME (date) FROM excelsior.clicks
WHERE url = 'http://google.com' ALLOW FILTERING;
The writetime output in microseconds converts to Sun, 14 Jul 2013
22:03:15 GMT or 3:03 pm Pacific time.
writetime(date)
------------------
1373839395324001