> For the complete documentation index, see [llms.txt](https://vikram-bajaj.gitbook.io/cs-gy-6083-principles-of-database-systems/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://vikram-bajaj.gitbook.io/cs-gy-6083-principles-of-database-systems/sql/dml-commands/string-operations.md).

# String Operations

## String Matching

The **like** keyword is used followed by:

* **%**: The character % matches any substring
* **\_**: The character \_ matches any character

```
select name from instructor where name like '%kr%'
```

This will return Vi**kr**am as one of the results.

## Other Supported String Operations

* Concatenation using ||
* Converting from uppercase to lowercase and vice versa
* Finding string length
* Extracting substrings etc.


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