> For the complete documentation index, see [llms.txt](https://cortex-docs.paloaltonetworks.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://cortex-docs.paloaltonetworks.com/cortex-xdr-3.x/cortex-xdr-3.x-documentation/cortex-xdr-xql/functions/replace.md).

# replace

**Syntax**

```programlisting
replace (<field>, "<old_substring>", "<new_string>")
```

**Description**

The `replace()` function accepts a string field, and replaces all occurrences of a substring with a replacement string.

**Examples**

If '.exe' is present on the `action_process_image_name` field value, replace that substring with an empty string. This example uses the [if](/cortex-xdr-3.x/cortex-xdr-3.x-documentation/cortex-xdr-xql/functions/if.md) and [lowercase](/cortex-xdr-3.x/cortex-xdr-3.x-documentation/cortex-xdr-xql/functions/lowercase.md) functions, as well as the contains operator to perform the conditional check.

```programlisting
dataset = xdr_data 
| fields action_process_image_name as apin 
| filter apin != null 
| alter remove_exe_process = if(lowercase(apin) contains ".exe",
                              replace(lowercase(apin),".exe",""),
                              lowercase(apin)) 
| limit 10
```

See also the [ltrim, rtrim, trim](/cortex-xdr-3.x/cortex-xdr-3.x-documentation/cortex-xdr-xql/functions/ltrim-rtrim-trim.md) function example.


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