How to resolve the failure of string truncation in Oracle’s substr function?

The syntax for extracting substrings in Oracle using the SUBSTR function is as follows:

Retrieve a portion of a string, starting from a specified position, with an optional length.

In this case, the “string” is the string to be extracted, “start_position” is the position to begin extraction, and “length” is optional, indicating the length to be extracted.

If you encounter any issues while using the SUBSTR function, make sure to consider the following points:

1. Confirm if the value of start_position is correct. start_position indicates the position from which to start extracting characters, and its value should be a positive integer. If start_position is less than 1 or greater than the length of the string, the extraction will not succeed.
2. Make sure that the value of “length” is correct. If “length” is not specified, the SUBSTR function will extract from the “start_position” to the end of the string. If a value for “length” is specified, the extracted length will be as specified by “length”. Please ensure that the value of “length” is greater than 0.
3. Make sure the value of the string is correct. Ensure that the provided string is valid and has a length greater than or equal to the start position.

Here are some examples of usage:

– Extract the string starting from the 3rd character.

Extract a 2-character string starting from the 3rd character.

If the issue persists, feel free to provide more information such as error messages or specific use cases to better assist you in resolving the problem.