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What Does json_extract_path() Function Do in PostgreSQL

The json_extract_path() function is a JSON function that is used to extract the values from the JSON data. The path of the values that are to be fetched is specified as an argument in the function.

How to Use WHERE Clause With Arrays in PostgreSQL?

Arrays are among the most commonly used data types in Postgres. In Postgres, the WHERE clause is used with arrays to get and update the records as per users requirements

How to Use SUM() Function with Group By Clause in PostgreSQL

The GROUP BY clause and SUM() function are used together when we want to calculate the sum of values based on the specific groups.

How to Create an Extension in PostgreSQL

In PostgreSQL, the extensions can be created by using the CREATE EXTENSION statement which is followed by the name of the extension.

Understanding Postgres Log Functions - ln(), log(), log10()

In PostgreSQL, the log functions are used to find the logarithm of a particular number(provided in the function as a parameter). These functions include: log(), ln(), and log10().

How to Drop an Extension in PostgreSQL

In PostgreSQL, the extensions can be dropped by using the DROP EXTENSION statement which is followed by the name of the extension.

How to Switch User in PostgreSQL

We can switch a user in PostgreSQL by simply executing the SET ROLE command. But the point to be noted is that we can only switch the user if it already exists.

How to Use Generated Columns in PostgreSQL

The generated columns do not have a fixed value; rather this value is automatically computed by the expression that is determined at the time of column definition.

How to Transpose Columns to Rows in PostgreSQL?

In PostgreSQL, the crosstab() function and the unnest() function are used to transpose columns into rows. These functions help us transform the table by returning the transposed table.

How to Select Random Rows in PostgreSQL

To get random rows from a database table, use the RANDOM() function with the ORDER BY clause. We can also specify the limit of the number of rows we want to fetch/retrieve.