I would like to know if there is a way to detect each time there is a new data inserted in a data table so that I can update a chart in my application.
I use postgreSQL, node.js, vue.js for the framework and chart js for the display.
CodePudding user response:
Assuming that the source database table contains an ID
column that is incremented by a SEQUENCE
, you can repeatedly select new data as follows:
SELECT * from <table name> where ID > :lastSelectedID
ORDER BY ID ASC;
In case the source table contains a column that holds the insertion date/time (i.e. CREATED
), the same could look as follows:
SELECT * from <table name> where CREATED > :lastSelectedCreated
ORDER BY CREATED ASC;;