PostgreSQL provides us with a couple of functions that allow us to pad strings. We can use these functions to put one or more space characters or other characters on either the right side, left side, or both sides of the string.
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4 Ways to List All Indexes in a SQL Server Database
By default, SQL Server creates indexes automatically when we do things like create certain constraints. We also have the option of creating indexes separately for our own (usually performance related) reasons. Either way, there may be times where we need to check what indexes we have in our database.
In this article, we’ll explore four ways to retrieve information about all indexes in a SQL Server database.
Continue readingFix Error 1909 “Cannot use duplicate column names in index” in SQL Server
If you’re getting SQL Server error 1909 that reads something like “Cannot use duplicate column names in index. Column name ‘FirstName’ listed more than once“, it appears that you’re trying to create an index, but you’re listing the same column multiple times.
Each column can only be listed once in the index definition.
To fix this issue, make sure each column is listed only once.
Continue readingWhat Does “Schema-Bound” Mean in SQL Server?
In SQL Server, “schema-bound” refers to a specific feature that ensures a SQL object, such as a view or function, is tightly linked to the schema of the underlying tables or other database objects it references. When a view or function is schema-bound, the underlying tables or objects cannot be altered in a way that would break the view or function’s dependencies.
Continue reading3 Ways to Concatenate Strings in PostgreSQL
When working with databases (and software in general), string concatenation is the operation of joining character strings end-to-end. For example if we have two words, we can combine them into one.
PostgreSQL provides us with multiple ways to concatenate strings. Below are two functions and one operator that we can use to concatenate strings in PostgreSQL.
Continue readingFix “The objects … in the FROM clause have the same exposed names” in SQL Server (Error 1013)
If you’re getting an error that reads something like “The objects “employees” and “employees” in the FROM clause have the same exposed names. Use correlation names to distinguish them’” in SQL Server, it could be that you’re trying to do a self-join without assigning table aliases.
When doing self-joins, we need to provide aliases for the tables so that SQL Server can distinguish between each instance.
To fix this issue, be sure to use unique table aliases in your query.
Continue readingHow to Log Data Changes with the SQL Server OUTPUT Clause
SQL Server has an OUTPUT clause that we can use any time we do an INSERT, UPDATE, DELETE, or MERGE operation. It allows us to retrieve information from modified rows during such operations. This can be especially useful for auditing, logging, or understanding the impact of database changes without needing an additional query.
Let’s look at how the OUTPUT clause can help us log the data changes in our database.
Using a CTE with a DELETE Statement in SQL Server to Remove Duplicates
Common Table Expressions (CTEs) are a nifty SQL feature that allow us to define a temporary result set, which can then be used in subsequent queries, including DELETE statements. In the context of removing duplicate data, a CTE can be helpful when we want to identify and remove only the duplicated rows, keeping one version of each unique record.
Let’s go through a step-by-step example of using a CTE with a DELETE statement to remove duplicate data.
Fix “Create View or Function failed because no column name was specified for column” in SQL Server (Error 4511)
If you’re getting an error that reads “Create View or Function failed because no column name was specified…” in SQL Server, perhaps you’re using a function or an arithmetic expression in the SELECT list, but you haven’t provided a name for the column.
As the error message alludes to, you need to provide a column name when doing stuff like that.
Continue readingUnderstanding Common Table Expressions (CTEs): A Beginner’s Guide
Common table expressions (CTEs) are a feature that we can use in SQL to help simplify complex queries and enhance readability. They can help with things like code readability, performance, recursive queries, and more.
This article explores what CTEs are, their syntax, types, use cases, and best practices, along with examples to help illustrate their usage.
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