After you update it, this value becomes the time of change in the record. When you insert a record, the value of the timestamp field is the default current time. Moddatetime plug-in applies to all PostgreSQL versions, as long as it is available. ![]() The results of the above example are as follows: db1=# create extension moddatetime ĭb1(# moddate timestamp DEFAULT CURRENT_TIMESTAMP NOT NULLĭb1-# EXECUTE PROCEDURE moddatetime (moddate) ĭb1=# INSERT INTO mdt VALUES (1, 'first') ĭb1=# INSERT INTO mdt VALUES (2, 'second') ĭb1=# INSERT INTO mdt VALUES (3, 'third') Moddate timestamp DEFAULT CURRENT_TIMESTAMP NOT NULL Here is an example of moddatetime: DROP TABLE mdt The type of this column should be timestamp or timestamp with the time zone. You should define a single trigger argument: the name of the column to be altered. Tracking the last modified time of a specific row in a table is straightforward using this plug-in.Ĭreating a BEFORE UPDATE trigger using this function allows you to utilize it. You can use the moddatetime() plug-in to save the current time into a timestamp field. moddatetime - Functions for Tracking Last Modification Time This plug-in also tracks and alters the modified value.į.36.4. The default value of the timestamp field is the current time when you use the moddatetime plug-in. PG supports this function in two methods:Ģ) Virtual columns Method 1: Trigger-Track Timestamp by moddatetime This is enough to help the recovery process determine the relative order of page modifications, but the timestamp value has nothing to do with the time. Each time a page is modified, it is marked with the current value, and then this value is increased by one. The timestamp data type was initially introduced to support the SQL Server recovery algorithm. It is a binary number that indicates the relative order of data modifications that occurred in the database. ![]() ![]() The data type of SQL Server timestamp is independent of time and date.
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