Postgres and Open Source Experts

Create a backup of the local PostgreSQL database and connect to the AWS RDS database. After that, simply restore the backup file to the RDS database.

Postgres allows us to utilize the for loop to loop through a query’s result set. A record-type variable can be declared to keep the rows of a result set returned by the SELECT query.

In Postgres, the “LOCALTIME” function is used to get the current time without zone information. It is executed without parentheses.

In PostgreSQL, the ORDER BY clause treats the null entries as the largest values. So, when a table is sorted ascendingly, then the null values will come at the bottom of the table.

Use the EXTRACT() or DATE_PART() function along with the “week” argument to get a week number from a particular date or timestamp.

In PostgreSQL, multiple columns can be used with the GROUP BY clause. Specify a comma between the columns to be grouped when using the GROUP BY clause on multiple columns.

A "must appear in the GROUP BY clause" error occurs in PostgreSQL when a column is specified in the SELECT statement but it is not utilized in the GROUP BY clause or any aggregate function.

JUSTIFY_INTERVAL() is a built-in DateTime function that utilizes the JUSTIFY_DAYS() and JUSTIFY_HOURS() functions with sign adjustments to adjust the intervals.

In PostgreSQL, a built-in DateTime function named JUSTIFY_HOURS() is used to adjust the 24-hour time periods to days.

In PostgreSQL, the “CLOCK_TIMESTAMP()” function helps us in getting the current DateTime of a database that may change during query execution.