# QueryKeyExists

This function returns true if the key exists in the query

## Method Signature

```
QueryKeyExists(query=[query], key=[string])
```

### Arguments

| Argument | Type     | Required | Description                    | Default |
| -------- | -------- | -------- | ------------------------------ | ------- |
| `query`  | `query`  | `true`   | The query to check for the key |         |
| `key`    | `string` | `true`   | The key to check for           |         |

## Examples

### Check to see if column exists in Query

Uses the member function syntax

[Run Example](https://try.boxlang.io/?code=eJxdjrEKwjAURefkKy6ZWgiCjoqbjtXFTRyCfWpoTTV5MRbx303VRbd7H%2Bc8rqMUMMc1ku9XlAooW2u23JLSOTumI3l9M35%2FMj6ftpDiIYXImMIUYz3kD5%2BrWlCiHjUdyHDAxsezcUqKp%2F6xJn9WZRySaZuAzqHqurcidyhnMnnLtI58iVzA5bGjhvrl3QYOeev3RTmQLzYjOmI%3D)

```java
news = queryNew( "id,title", "integer,varchar", [ 
	{
		"id" : 1,
		"title" : "Dewey defeats Truman"
	},
	{
		"id" : 2,
		"title" : "Man walks on Moon"
	}
] );
writeOutput( news.keyExists( "title" ) );

```

Result: true

### Additional Examples

[Run Example](https://try.boxlang.io/?code=eJzLrQwsTS2qVLBVKATRfqnlGgpKyaXFJZ4uOiDKLzE3VUlB05qrvCizJNWlNLdAA6LSO7XStSKzuKRYQyEXYoaOglJiOkgx0cqRLADpAQBbsC8%2F)

```java
myQuery = queryNew( "custID,custName" );
writeDump( queryKeyExists( myQuery, "age" ) );
writeDump( queryKeyExists( myQuery, "custName" ) );

```

## Related

* [QueryAddColumn](/boxlang-language/reference/built-in-functions/query/queryaddcolumn.md)
* [QueryAddRow](/boxlang-language/reference/built-in-functions/query/queryaddrow.md)
* [QueryAppend](/boxlang-language/reference/built-in-functions/query/queryappend.md)
* [QueryClear](/boxlang-language/reference/built-in-functions/query/queryclear.md)
* [QueryColumnArray](/boxlang-language/reference/built-in-functions/query/querycolumnarray.md)
* [QueryColumnCount](/boxlang-language/reference/built-in-functions/query/querycolumncount.md)
* [QueryColumnData](/boxlang-language/reference/built-in-functions/query/querycolumndata.md)
* [QueryColumnExists](/boxlang-language/reference/built-in-functions/query/querycolumnexists.md)
* [QueryColumnList](/boxlang-language/reference/built-in-functions/query/querycolumnlist.md)
* [QueryCurrentRow](/boxlang-language/reference/built-in-functions/query/querycurrentrow.md)
* [QueryDeleteColumn](/boxlang-language/reference/built-in-functions/query/querydeletecolumn.md)
* [QueryDeleteRow](/boxlang-language/reference/built-in-functions/query/querydeleterow.md)
* [QueryEach](/boxlang-language/reference/built-in-functions/query/queryeach.md)
* [QueryEvery](/boxlang-language/reference/built-in-functions/query/queryevery.md)
* [QueryFilter](/boxlang-language/reference/built-in-functions/query/queryfilter.md)
* [QueryGetCell](/boxlang-language/reference/built-in-functions/query/querygetcell.md)
* [QueryGetResult](/boxlang-language/reference/built-in-functions/query/querygetresult.md)
* [QueryInsertAt](/boxlang-language/reference/built-in-functions/query/queryinsertat.md)
* [QueryMap](/boxlang-language/reference/built-in-functions/query/querymap.md)
* [QueryNew](/boxlang-language/reference/built-in-functions/query/querynew.md)
* [QueryNone](/boxlang-language/reference/built-in-functions/query/querynone.md)
* [QueryPrepend](/boxlang-language/reference/built-in-functions/query/queryprepend.md)
* [QueryRecordCount](/boxlang-language/reference/built-in-functions/query/queryrecordcount.md)
* [QueryRecordCount](/boxlang-language/reference/built-in-functions/query/queryrecordcount.md)
* [QueryReduce](/boxlang-language/reference/built-in-functions/query/queryreduce.md)
* [QueryRegisterFunction](/boxlang-language/reference/built-in-functions/query/queryregisterfunction.md)
* [QueryReverse](/boxlang-language/reference/built-in-functions/query/queryreverse.md)
* [QueryRowData](/boxlang-language/reference/built-in-functions/query/queryrowdata.md)
* [QueryRowSwap](/boxlang-language/reference/built-in-functions/query/queryrowswap.md)
* [QuerySetCell](/boxlang-language/reference/built-in-functions/query/querysetcell.md)
* [QuerySetRow](/boxlang-language/reference/built-in-functions/query/querysetrow.md)
* [QuerySlice](/boxlang-language/reference/built-in-functions/query/queryslice.md)
* [QuerySome](/boxlang-language/reference/built-in-functions/query/querysome.md)
* [QuerySort](/boxlang-language/reference/built-in-functions/query/querysort.md)


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/query/querykeyexists.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.