The ‘LENGTH’ function in SQL is utilized to determine the length of a string, measured by the number of characters it contains.

This function is a built-in feature of SQL designed to return the character count of a specified string. The syntax for employing the ‘LENGTH’ function is as follows:

In this syntax, ‘string’ represents the input parameter for which you wish to ascertain the length. The function will yield an integer value that indicates the total number of characters present in the string.

For instance, consider a table named ‘Students’ that has a column called ‘Name’. If you wish to calculate the length of each student’s name, you can use the ‘LENGTH’ function in the following SQL query:

Executing this SQL statement will return a result set comprising two columns: the first column will display each student’s name, while the second column will show the corresponding length of that name.

It’s important to highlight that the ‘LENGTH’ function counts all characters, including spaces and punctuation marks. For example, if a student’s name is ‘John Doe’, the ‘LENGTH’ function will return $8$, since it counts the space between ‘John’ and ‘Doe’ as a character.

The ‘LENGTH’ function proves to be quite valuable in various scenarios. For example, it can be used to validate data within your database by ensuring that certain fields contain the correct number of characters. Additionally, it can facilitate data analysis, such as calculating the average length of strings in a particular field.

Keep in mind that the ‘LENGTH’ function adheres to the SQL standard, which implies that it should function in any relational database management system (RDBMS) that supports SQL. However, the exact syntax and behavior may differ slightly among various RDBMS platforms, so it’s advisable to consult the documentation specific to your system if you have any uncertainties.