Hierarchical data in SQL is data represented in a tree-like structure. The hierarchical data is a parent-child structure where each child has one parent. Each node can have one, more, or zero child nodes. The hierarchical type of data is very common among file systems, product categories, etc. This article is based on the methods to handle the hierarchical …
SQL auto-increment is a specific technique to create some unique numbers as a value to be stored in the tables. Database records, as a result, need specific primary keys while adding new rows to the database. It can also be done without any manual override with the help of the auto-increment feature. This article gives a detailed definition of auto-increment or key uniqueness. To keep it simple, we will …
In business intelligence and data analysis, the analysis of the operation performance metrics against the historical trend is a vital process that contributes to understanding the trends, the opportunity for growth and the taking of right decisions. Such comparison is important because year-over-year difference analysis acts as the basic tool for analysts and business entities …
Calculating Year-Over-Year Difference in SQL: An Easy Guide Read More »
The NULLs in SQL play an essential role in defining the ‘unknown values’ from the database. In SQL, almost every database contains such types of values to represent the empty spaces. The comparison operators ( =, <>, <, > ) are widely used in SQL queries to solve complex models. In this article, we are …
Comparison Operators With NULLs In SQL: IS NULL and IS NOT NULL Read More »
PostgreSQL is the open-source with the free functionality that you can use to perform certain tasks. The ability of the PostgreSQL language is upgraded with various extensions that will be applicable for different kinds of models for operation complexity. Here, we are going to analyze the aggregate function PostgreSQL GROUP BY extension deeply. The GROUP …
GROUP BY Extensions in PostgreSQL: An Easy Guide Read More »
SQL language provides a wide variety of functions, clauses, JOINs, etc. that help to provide additional features to solve complex problems. One more thing that SQL language has is the CTE. CTE stands for ‘Common Table Expression’. It’s a momentary result set that you can reference within a SELECT, INSERT, UPDATE, or DELETE statement in …
We can face many errors while implementing various queries in SQL. Different errors arise due to wrong syntax or implementation defects. In this article, we are going to review the error handling techniques for one of the common errors which is ‘MySQL.user’ is not of type ‘base table’. The error message ‘MySQL.user’ is not of …
How To Fix Error ‘MySQL.user’ is not of type ‘base table’ – Easy Guide Read More »
In different Machine learning and Data analytics models, we have to deal with large datasets with an ‘N’ number of columns and rows. Sometimes, we need to find the difference between the data values of the rows. In this article, we will see some queries to find the difference between the rows. Let’s start with …
Calculating the Difference Between Two Rows in SQL Read More »
For different business models, we need to use financial analysis techniques that help us analyze the business adequately. The financial analysis carried out in a business model is important as it helps to determine the weaknesses and strengths of different factors involved with the investment. The SQL queries enable financial analysis of different business models. …
We handle databases with the help of SQL queries. Complex problems require logical solutions. These logical solutions may be long sometimes. Problems based on data pipelines require very lengthy solutions. These types of queries are 1000 lines long in some cases. The long SQL queries contain different functions, clauses, and joins. Sometimes, queries also consist …
How to Organize Long SQL Queries: A Detailed Guide Read More »