Postgres and Open Source Experts

To query the ARRAY data in Postgres, the SELECT statement is used. Postgres allows us to query the data of an entire array or a specific array index.

In PostgreSQL, different built-in functions are used along with the SELECT statement to query date and time. This blog post explained how to query date and time in Postgres using suitable examples.

In Postgres, the COUNT() function finds duplicate records. While the “DELETE USING” statement drops the duplicates.

The REPEAT() function in Postgres is a string function that retrieves a string consisting of the given string repeated an ‘n’ number of times.

To get a day from a date, specify the “Day” as the first argument and a specific date, timestamp, or interval as the second argument to the EXTRACT().

In PostgreSQL, the SQRT() is a built-in mathematical function that accepts a positive numeric value and retrieves its square root.

PostgreSQL provides a built-in math function named MOD() that accepts numeric values as arguments, performs division, and retrieves the remainder after division.

The DIV() and MOD() functions in Postgres perform the division on numeric values. However, the DIV() function retrieves a quotient while the MOD() function retrieves the remainder.

The RIGHT() function takes a string and the number of characters to extract as arguments and retrieves the extracted/modified string.

SQL Shell supports various commands and queries to describe the Postgres tables, such as “\d”, “\d+”, information_schema, etc.