Strings are a fundamental part of any database administrator or programmer. They allow you to store textual information within a database.
This article will discuss how you can determine the length of a string type in Standard SQL.
In Standard SQL, there are three main methods to determine the length of a string.
SQL Byte Length Function
The first method you can use to determine the length of a string is the byte_length function. This function takes the string as the input parameter and returns the length of the string in bytes.
The function syntax is shown below:
Keep in mind that the function’s return type is a 64-bit integer.
An example usage is shown below:
BYTE_LENGTH('Hello') AS lenght_in_bytes;
The example statement takes the string “Hello” and returns its length in bytes. An example output is as shown:
5
SQL Char_Length Function
The second method you can use to determine the length of a string is the char_length function. Similarly, the function takes a string and returns the length of the string in characters.
The function syntax is shown below:
An example usage is shown below:
CHAR_LENGTH('Hello') AS lenght_in_characters;
This should return the output as shown:
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Note that in some cases, you may find this function renamed to CHARACTER_LENGTH(). However, the functionality remains the same.
SQL Length Function
The final and most common method to determine string length is the length() function. The function accepts a string or byte type. It then returns the length of the input value in characters (for a string) or bytes (for byte type).
The function syntax is as shown:
We can illustrate example usage as shown below:
LENGTH('Hello world') AS LENGTH;
The resulting output is as shown:
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Closing
This article discusses three main methods you can use to determine the length of a string in Standard SQL.
