Apache Solr Reference Guide Covering Apache Solr 6.0

Transforming Result Documents
Document Transformers can be used to modify the information returned about each documents in the results of
a query.
Using Document Transformers
When executing a request, a document transformer can be used by including it in the fl parameter using square
brackets, for example:
fl=id,name,score,[shard]
Some transformers allow, or require, local parameters which can be specified as key value pairs inside the
brackets:
fl=id,name,score,[explain style=nl]
As with regular fields, you can change the key used when a Transformer adds a field to a document via a prefix:
fl=id,name,score,my_val_a:[value v=42 t=int],my_val_b:[value v=7 t=float]
The sections below discuss exactly what these various transformers do.
Available Transformers
[value] - ValueAugmenterFactory
Modifies every document to include the exact same value, as if it were a stored field in every document:
q=*:*&fl=id,greeting:[value v='hello']
The above query would produce results like the following:
1
hello
...
By default, values are returned as a String, but a " t" parameter can be specified using a value of int, float,
double, or date to force a specific return type:
q=*:*&fl=id,my_number:[value v=42 t=int],my_string:[value v=42]
In addition to using these request parameters, you can configure additional named instances of
ValueAugmenterFactory, or override the default behavior of the existing [value] transformer in your
solrconfig.xml file:
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