If you’re getting SQL Server error 11415 that reads something like “Object ‘UQ_Employees_Email’ cannot be disabled or enabled. This action applies only to foreign key and check constraints“, it’s probably because you’re trying to disable either a DEFAULT, UNIQUE or PRIMARY KEY constraint.
Category: DBMS
Database Management Systems
Nested WHILE Loops in SQL Server: A Beginner’s Guide with Examples
WHILE loops are a fundamental concept in T-SQL programming, allowing us to execute a block of code repeatedly as long as a specified condition is true. Nested WHILE loops take this concept further by placing one WHILE loop inside another, enabling more complex iterations.
This guide will walk you through the basics of nested WHILE loops in SQL Server, complete with simple examples and a demonstration of the BREAK statement.
Understanding the Difference Between SCALE(), MIN_SCALE() and TRIM_SCALE() in PostgreSQL
Anyone who looks at PostgreSQL’s list of mathematical functions will notice that there are some functions that have “scale” in their name. In particular, scale(), min_scale(), and trim_scale().
While these functions all have a similar name, they each have a different purpose. That said, they’re all related to the scale of the given number. The scale is the number of digits to the right of the decimal point in a number. For example, the number 1.95 has a scale of 2, and 1.958 has a scale of 3.
Continue readingFix Error 1987 “Cannot alter nonclustered index … because its clustered index is disabled” in SQL Server
If you’re getting SQL Server error 1987 that reads something like “Cannot alter nonclustered index ‘UQ_Employees_Email’ on table ‘Employees’ because its clustered index is disabled“, it’s probably because you’re trying to rebuild a nonclustered index when the clustered index for the table is disabled.
To fix this issue, either enable/rebuild the table’s clustered index first, then try again, or enable all indexes at once.
The clustered index will typically be the primary key index (unless you’ve specified another clustered index for the table).
Continue readingHow to Delete a UNIQUE Constraint in SQL Server
If you’ve got a table that has a UNIQUE constraint, there may come a time where you need to remove it. Whether it’s a permanent thing or temporary, you can easily delete the constraint using the following method.
What is a Synonym in SQL Server?
In SQL Server, a synonym is a database object that provides an alternative name for another database object, such as a table, view, stored procedure, or function. Synonyms act as aliases, allowing us to reference objects using different names without changing the underlying object itself.
The underlying object that the synonym references is typically referred to the base object. Either way, the synonym allows us to reference the base object without actually referring to its name (we refer to the synonym’s name instead).
Continue readingFix Error 4512 “Cannot schema bind view” in SQL Server Due to “two-part format” Issue
If you’re getting an error that reads something like “Cannot schema bind view ‘vEmployees’ because name ‘Employees’ is invalid for schema binding. Names must be in two-part format and an object cannot reference itself” it could be that you’re trying to create a schema bound view, but you’re not using a two-part format for names (such as the table names within the view).
Continue reading2 Ways of Creating a Composite Type in PostgreSQL
In PostgreSQL, a composite type is a data type that represents the structure of a row or record. It’s basically a list of field names and their data types.
We can use composite types in many of the same ways we can use simple types, such as in table columns.
Below are two ways of creating composite types in PostgreSQL.
Continue readingFix Error 1505 “The CREATE UNIQUE INDEX statement terminated because a duplicate key was found for the object name” in SQL Server
If you’re getting an error that reads something like “The CREATE UNIQUE INDEX statement terminated because a duplicate key was found for the object name” it’s probably because you’re trying to create a UNIQUE constraint on a column that already contains duplicate values.
List of Array Functions in PostgreSQL
Below is an alphabetical list of functions that we can use when working with arrays in PostgreSQL.
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