![]() ![]() It guides you through the basics of SQL, including string comparison.While you can use a scalar function such as UPPER or LOWER and you can re-collate the column so that it's no longer case sensitive, these approaches all require data conversion be done against the base data which will never allow for an index seek. If you haven’t heard about them or you don’t feel confident using them, you may want to check the SQL Basics course. If you’re new to SQL, these terms may be confusing. In this section, we have mentioned concepts as LIKE and string comparisons. In all three DBMSs, you can change the collation setting to modify the default behavior. This means WHERE column = 'abc' returns TRUE for e.g., 'abc', 'ABC', or 'aBc'. In contrast, MySQL and MS SQL Server have case-insensitive behaviors by default. To do a case-insensitive comparison, use the ILIKE keyword e.g., column ILIKE 'aBc' and column ILIKE 'ABC' both return TRUE for 'abc'. column LIKE 'ABC' or column LIKE 'aBc' will return FALSE for such comparison. This means WHERE column = 'abc' returns TRUE only for values in the column exactly equal to 'abc'. Fortunately, though, this one is simpler.īy default, PostgreSQL performs a case-sensitive string comparison. It also differs a little based on the DBMS. Last but not least, let's talk about column values. If you’re new to SQL, we recommend reading the article “ 6 Common SQL Syntax Mistakes All Learners Make,” which helps you with the most common errors everyone gets at the beginning of the SQL journey. For this reason, you need to understand the error messages you can get. In MS SQL Server, the most common practice is to use PascalCase.ĭifferences in case sensitivity can lead to problems in executing your queries. In PostgreSQL and MySQL, table names are most often written in lowercase (or more precisely, snake_case). Have a clear code style in your projects so that it’s easier to read and navigate. Keep in mind: even though you can use different cases for your code, it doesn’t mean you should. By default, it’s case-insensitive, and like with MySQL, you can change this behavior by modifying the collation setting. However, you can change the behavior by changing collation. ![]() This means MySQL is case-insensitive in Windows and macOS, while it is case-sensitive in most Linux systems. ![]() By default, it depends on the operating system and its case sensitivity. This is due to by default collation of the Database set. This forces PostgreSQL to be case-sensitive for table names. When searching for partial strings in MySQL with LIKE OR you will match case-insensitive by default. However, you can easily modify this by adding double quotation marks (") to the table name. This behavior doesn’t depend on the operating system. ![]() In this database, table names are case-insensitive. For more information, refer to your DBMS documentation. We’ll focus on the three most popular relational databases, all of which are taught at : PostgreSQL, MySQL, and MS SQL Server. We won’t discuss the topic in detail, as there are many ways to customize the behavior. The user can also impact case sensitivity. In addition, the behavior depends on the operating system (i.e., Windows, macOS, or Linux). Unfortunately, different DBMSs work differently. This topic is a little bit more complicated. Are SQL Table and Column Names Case-Sensitive? If you’re still at the beginning of your programming journey, you may want to know how to learn the SQL syntax, as learning the syntax also includes learning keywords. You may have different courses with different projects, and switching between them is less time-consuming with a clear code style. This also applies if you’re a student collaborating with other students. Most often, SQL keywords are written in capital letters. This way, everyone will read and understand the code quicker. This means you’ll have to read each other's code.īecause of this, you need a convention whether to write keywords in all capital letters, capitalize only the first letter, or leave everything in lowercase letters. If you’re thinking about working professionally with SQL, you have to consider it involves collaborating with other engineers. Unfortunately, it is a little bit different in practice. The computer doesn’t care whether you write SELECT, select, or sELeCt so, in theory, you can write however you like. Keywords in SQL are case-insensitive for the most popular DBMSs. ![]()
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