In SQL databases, the TRUNCATE statement can be used to quickly remove all data from a table. Unlike the DELETE statement, TRUNCATE is typically faster and uses fewer system resources, especially for large tables.
In this article, we’ll explore the TRUNCATE statement, its usage, and provide some examples.
The PostgreSQL split_part() function splits a string based on a specified delimiter and then returns the specified part from the split string.
The function accepts three arguments; the string, the delimiter, and the part that we want to return.
Continue readingIn PostgreSQL, we can use the pg_client_encoding() function to get the current client encoding name.
Temporal tables, introduced in SQL Server 2016, provide a powerful mechanism for tracking historical changes to data. This feature is particularly useful for auditing purposes, allowing organisations to maintain a complete history of data modifications without the need for complex triggers or custom logging solutions.
In this article, we’ll explore how to implement and use temporal tables for auditing in SQL Server, along with examples to demonstrate.
Continue readingThe SQL SELECT statement is possibly the most commonly used SQL statement. It’s often used to return data from a database, but it can also be used to call functions that return data. The SELECT statement can also be used to return static values, such as string literals.
But the SELECT statement isn’t the only way we can return data in SQL. Another way to return values is with the VALUES statement.
In PostgreSQL the right() function returns the specified number of rightmost characters in a given string.
We have the option of specifying the number of characters to return from the right or the number of characters to omit from the left. We do this by specifying a positive integer (to return n number of rightmost characters) or a negative integer (to return everything except n leftmost characters).
Continue readingIn PostgreSQL we can use the left() function to get the specified number of leftmost characters in a given string.
We have the option of specifying the number of characters to return from the left or the number of characters to omit from the right. We do this by specifying a positive integer (to return n number of leftmost characters) or a negative integer (to return everything except n rightmost characters).
Continue readingThe WHILE loop in SQL Server is a control-flow statement that allows us to repeatedly execute a block of code as long as a specified condition is true. It’s useful for iterative tasks and processing data in batches.
In PostgreSQL, erfc() is a mathematical function that provides the mathematical complementary error function, without loss of precision for large inputs. It returns 1 - erf(x).
The erfc() function was introduced in PostgreSQL 16, which was released on September 14th 2023.
When we create an IDENTITY column in PostgreSQL, we have the option of specifying our own values for the sequence object that’s created.
This article provides an example of creating an IDENTITY column with our own sequence options.