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How Does the pi() Function Work in PostgreSQL?

Use the pi() function in PostgreSQL to get the mathematical constant value of π. pi() can be used in mathematical expressions to use the value of π.

PL/pgSQL Block Structure

PL/pgSQL supports block structure. The block has two sections; a declaration and a body. Sub-block structure is also supported by PL/pgSQL.

PostgreSQL Full-Text Search

In PostgreSQL, the full-text search returns all the possible results for the searched terms and their variants as well which was a drawback of the simple search approach.

SELECT if String Contains a Substring Match in PostgreSQL

SELECT if String Contains a Substring Match in PostgreSQL can be accomplished using different methods, such as LIKE and ILIKE, position(), substring(), etc.

UNION Vs INTERSECT Vs EXCEPT: What's the Difference

In Postgres, the UNION, INTERSECT, and EXCEPT are the set operators that are applied on at least two tables to get a specific combined result.

What Does the UPDATE ... FROM Statement Do in PostgreSQL

In PostgreSQL, the UPDATE FROM statement is used to update the data/row of any table according to the data of another table.

How to Comment Characters in psql

Commenting on the special character in psql may be a problem sometimes. To avoid errors we can use different methods, such as \echo, \warn, “\\” separator, etc.

How to Fix “window function nth_value requires an OVER clause” in Postgres

In PostgreSQL, the error “window function nth_value requires an OVER clause” occurs when the OVER clause is not specified in the query.

How to Drop a Custom/User-Defined Type in PostgreSQL

In PostgreSQL, an already existing user-defined data type that is no longer in our use can be dropped by using the DROP TYPE IF EXISTS statement.

How to Use DISTINCT ON Expression in Postgres

In PostgreSQL, the DISTINCT ON clause works similarly to the DISTINCT clause as it returns the unique records of data after discarding the duplicate records.