## Syntax
```mermaid
%%{init: {
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'themeVariables': {
'fontSize': '11px',
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flowchart LR
Start((START)) --> IS_GUID[IS_GUID]:::quoted
IS_GUID --> End((END))
```
## Purpose
The `IS_GUID` SQL function evaluates to true when a value is representing a valid GUID. A valid GUID can be cast to a `guid` value using [[TO_GUID]].
Parameters:
- Input (`ANY`): value to test whether a cast to `guid` is possible.
Returns: true when the value can be cast to a GUID, false otherwise.
## Examples
The following example determines whether `'f5c3dea4-02f5-4230-b72c-cc61a434a082'` can be cast to a `guid`:
```sql
select is_guid('f5c3dea4-02f5-4230-b72c-cc61a434a082')
----------------
true
```
The following example determines whether `'1234567890'` can be cast to a `guid`:
```sql
select is_guid('1234567890')
----------------
false
```