Search results
Exploring an important, yet often misunderstood concept in SQL: `NULL` values. We'll also include hands-on examples with a sample dataset.
What is a NULL Value? A field with a NULL value is a field with no value. If a field in a table is optional, it is possible to insert a new record or update a record without adding a value to this field. Then, the field will be saved with a NULL value.
20 cze 2024 · This tip will help you understand what NULL means in the context of the Microsoft Fabric data universe, which includes SQL Server. It will then show how these values can make queries act unexpectedly and how to best interact with NULL values to avoid problems.
26 kwi 2023 · I want to understand what NULL values are in T-SQL and how to work with them in a SQL database. Are they the same as zero? Is it an unknown value? Can I use a NULL value in an arithmetic equation?
10 cze 2023 · NULL values represent an unknown value and are often found in SQL statements and table columns. They behave differently to other values and you need to be aware of some differences, especially when working with NOT IN and NOT EXISTS.
4 sty 2024 · In SQL Server, NULL represents the absence of a value in a column. It signifies missing or undefined data, distinct from zero or an empty string. SQL Server uses a three-valued logic, and handling NULL is crucial for accurate querying and reporting.
Learn what NULL values are in SQL, why they matter for database integrity, and how to handle them in operations to ensure accurate results and efficient data manipulation.
