SQL SUBSTR Function Explained

The SUBSTR function in SQL is used to extract a substring from a string. Essentially, the SUBSTR function extracts a specified length of characters starting from a given position in a string.

The typical grammar format is as follows:

SUBSTR(string, start, length)

1. Original string from which to extract the substring.
2. Start: The starting position of the substring (index starts at 1).
3. length: the length of the substring to be extracted.

For example, if we have a string ‘Hello, World!’ and we want to extract the substring ‘World’ from it, we can use the following SQL query:

SELECT SUBSTR('Hello, World!', 8, 5);

The above query will return the result as ‘World’.