# Retrieving fields from \_source that don't have mappings?

**URL:** <https://discuss.elastic.co/t/retrieving-fields-from--source-that-dont-have-mappings/5319>\
**Category:** Elasticsearch\
**Created:** [September 6, 2011, 10:50pm UTC](https://discuss.elastic.co/t/retrieving-fields-from--source-that-dont-have-mappings/5319 "2011-09-06T22:50:57Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![ppearcy](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/ppearcy/32/980_2.png) [@ppearcy](https://discuss.elastic.co/u/ppearcy)\
**Post date:** [September 6, 2011, 10:50pm UTC](https://discuss.elastic.co/t/retrieving-fields-from--source-that-dont-have-mappings/5319/1 "2011-09-06T22:50:57Z")

</div>

Hey,  
I'm currently using 0.17.2 release. At some point in the past, in  
order to pull fields from the \_source without pulling back the entire  
\_source item, it was required to use script fields. So to set the  
script field, it looked like this:

```
	for (String field : params.returnFields) {
		String fieldLower = field.toLowerCase();

		// This script is in the default mvel
		// This script will pull the values we need from the source field,

```

without  
// needing to pull all the content over the wire. Documents with  
large amounts  
// of full text content benefit from this.  
Map\<String, Object\> searchParams = new HashMap\<String, Object\>();  
searchParams.put("fieldName", fieldLower);  
searchBuilder.addScriptField(fieldLower, "\_source[fieldName]",  
searchParams);  
}

And getting the value back looked like this:

```
public String getReturnValue(String Name, SearchHit hit) {
	String value = (String)hit.getFields().get(Name).value();
	if (value == null)
		value = "";

	return value;
}

```

I noticed that this no longer seemed to be the case and moved to doing  
things like this:

```
	for (String field : params.returnFields) {
		String fieldLower = field.toLowerCase();
		searchBuilder.addFields(fieldLower);
	}

public String getReturnValue(String Name, SearchHit hit) {
	String value;
	SearchHitField returnField = hit.getFields().get(Name);
	if (returnField == null) {
		value = "";
	} else {
		value = (String)returnField.value();
		if (value == null)
			value = "";
	}

	return value;
}

```

This worked fine for any fields that mapping were enabled for.  
However, for fields that are retrievable only, I have not been setting  
any mappings and just adding them to the \_source. However, it appears  
that fields must have mappings enabled for the second method to work.

I can get things to work by adding mappings that define the  
retrievable only fields as store=no and index=no, which is reasonable,  
but was curious if the second method was possible without adding the  
mappings for each retrievable field.

Thanks!  
Paul

---

<div class="post-metadata">

**Author:** ![kimchy](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/kimchy/32/44952_2.png) [@kimchy](https://discuss.elastic.co/u/kimchy)\
**Post date:** [September 7, 2011, 7:11am UTC](https://discuss.elastic.co/t/retrieving-fields-from--source-that-dont-have-mappings/5319/2 "2011-09-07T07:11:04Z")

</div>

You can still use script fields, and specify something like  
\_source.obj1.obj2. Or, you can also specify it in the fields section, though  
for fields without mappings, you should prefix it with \_source in fields as  
well.

On Wed, Sep 7, 2011 at 1:50 AM, ppearcy [ppearcy@gmail.com](mailto:ppearcy@gmail.com) wrote:

> Hey,  
> I'm currently using 0.17.2 release. At some point in the past, in  
> order to pull fields from the \_source without pulling back the entire  
> \_source item, it was required to use script fields. So to set the  
> script field, it looked like this:
> 
> ```
> for (String field : params.returnFields) {
> String fieldLower = field.toLowerCase();
> 
> // This script is in the default mvel
> // This script will pull the values we need from the
> 
> ```
> 
> source field,  
> without  
> // needing to pull all the content over the wire.  
> Documents with  
> large amounts  
> // of full text content benefit from this.  
> Map\<String, Object\> searchParams = new  
> HashMap\<String, Object\>();  
> searchParams.put("fieldName", fieldLower);  
> searchBuilder.addScriptField(fieldLower,  
> "\_source[fieldName]",  
> searchParams);  
> }
> 
> And getting the value back looked like this:
> 
> ```
> public String getReturnValue(String Name, SearchHit hit) {
> String value = (String)hit.getFields().get(Name).value();
> if (value == null)
> value = "";
> 
> return value;
> }
> 
> ```
> 
> I noticed that this no longer seemed to be the case and moved to doing  
> things like this:
> 
> ```
> for (String field : params.returnFields) {
> String fieldLower = field.toLowerCase();
> searchBuilder.addFields(fieldLower);
> }
> 
> public String getReturnValue(String Name, SearchHit hit) {
> String value;
> SearchHitField returnField = hit.getFields().get(Name);
> if (returnField == null) {
> value = "";
> } else {
> value = (String)returnField.value();
> if (value == null)
> value = "";
> }
> 
> return value;
> }
> 
> ```
> 
> This worked fine for any fields that mapping were enabled for.  
> However, for fields that are retrievable only, I have not been setting  
> any mappings and just adding them to the \_source. However, it appears  
> that fields must have mappings enabled for the second method to work.
> 
> I can get things to work by adding mappings that define the  
> retrievable only fields as store=no and index=no, which is reasonable,  
> but was curious if the second method was possible without adding the  
> mappings for each retrievable field.
> 
> Thanks!  
> Paul

---

<div class="post-metadata">

**Author:** ![ppearcy](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/ppearcy/32/980_2.png) [@ppearcy](https://discuss.elastic.co/u/ppearcy)\
**Post date:** [September 8, 2011, 4:14pm UTC](https://discuss.elastic.co/t/retrieving-fields-from--source-that-dont-have-mappings/5319/3 "2011-09-08T16:14:04Z")

</div>

Sweet, that works great. Thank you!

On Sep 7, 1:11 am, Shay Banon [kim...@gmail.com](mailto:kim...@gmail.com) wrote:

> You can still use script fields, and specify something like  
> \_source.obj1.obj2. Or, you can also specify it in the fields section, though  
> for fields without mappings, you should prefix it with \_source in fields as  
> well.
> 
> On Wed, Sep 7, 2011 at 1:50 AM, ppearcy [ppea...@gmail.com](mailto:ppea...@gmail.com) wrote:
> 
> > Hey,  
> > I'm currently using 0.17.2 release. At some point in the past, in  
> > order to pull fields from the \_source without pulling back the entire  
> > \_source item, it was required to use script fields. So to set the  
> > script field, it looked like this:
> 
> > ```
> > for (String field : params.returnFields) {
> > String fieldLower = field.toLowerCase();
> > 
> > ```
> 
> > ```
> > // This script is in the default mvel
> > // This script will pull the values we need from the
> > 
> > ```
> > 
> > source field,  
> > without  
> > // needing to pull all the content over the wire.  
> > Documents with  
> > large amounts  
> > // of full text content benefit from this.  
> > Map\<String, Object\> searchParams = new  
> > HashMap\<String, Object\>();  
> > searchParams.put("fieldName", fieldLower);  
> > searchBuilder.addScriptField(fieldLower,  
> > "\_source[fieldName]",  
> > searchParams);  
> > }
> 
> > And getting the value back looked like this:
> 
> > ```
> > public String getReturnValue(String Name, SearchHit hit) {
> > String value = (String)hit.getFields().get(Name).value();
> > if (value == null)
> > value = "";
> > 
> > ```
> 
> > ```
> > return value;
> > }
> > 
> > ```
> 
> > I noticed that this no longer seemed to be the case and moved to doing  
> > things like this:
> 
> > ```
> > for (String field : params.returnFields) {
> > String fieldLower = field.toLowerCase();
> > searchBuilder.addFields(fieldLower);
> > }
> > 
> > ```
> 
> > ```
> > public String getReturnValue(String Name, SearchHit hit) {
> > String value;
> > SearchHitField returnField = hit.getFields().get(Name);
> > if (returnField == null) {
> > value = "";
> > } else {
> > value = (String)returnField.value();
> > if (value == null)
> > value = "";
> > }
> > 
> > ```
> 
> > ```
> > return value;
> > }
> > 
> > ```
> 
> > This worked fine for any fields that mapping were enabled for.  
> > However, for fields that are retrievable only, I have not been setting  
> > any mappings and just adding them to the \_source. However, it appears  
> > that fields must have mappings enabled for the second method to work.
> 
> > I can get things to work by adding mappings that define the  
> > retrievable only fields as store=no and index=no, which is reasonable,  
> > but was curious if the second method was possible without adding the  
> > mappings for each retrievable field.
> 
> > Thanks!  
> > Paul

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [July 6, 2017, 3:55am UTC](https://discuss.elastic.co/t/retrieving-fields-from--source-that-dont-have-mappings/5319/4 "2017-07-06T03:55:03Z")

</div>