Using dynamic fields
Using dynamic fields, you can index content in fields that are not explicitly defined by the schema. A common use case for dynamic fields is to identify fields that should not be indexed or to implement a schema-less index.
Search schema fields that are dynamic and multiValued are not supported in CQL-based search indexes.
Spatial subfields prefix naming conventions
Dynamic fields for spatial subfields use prefix naming conventions to enable using map types to store geospatial data:
<types>
<fieldType class="solr.LatLonType" multiValued="false" name="LatLonType" subFieldPrefix="llt_"/>
<fieldType name="tdouble" class="solr.TrieDoubleField" precisionStep="8" positionIncrementGap="0"/>
</types>
<fields>
<dynamicField indexed="true" name="latmap*" stored="true" type="LatLonType"/>
<dynamicField name="llt_*" type="tdouble" indexed="true" stored="true"/>
</fields>
Best practices
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Avoid or limit the use of dynamic fields.
Apache Lucene® allocates memory for each unique field (column) name. For example, for a row with columns A, B, C, and another row with B, D, E, Lucene allocates 5 chunks of memory. For millions of rows, the heap is unwieldy.
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Instead of using dynamic fields, use a default query field, and then perform queries against the combined field.
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Use the
FieldInputTransformer(FIT) API.
To use a dynamic field
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Include an Apache Solr™ dynamic field in the search index schema.
Name the field using a wildcard at the beginning or end of the field. For example, an asterisk prefix or suffix in the field name in the schema designates a dynamic field.
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dyna_* -
*_s
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To define the map collection column in CQL, use the same base name (no asterisk) that you used for the field in search index schema.
For example, use
dyna_*in the search index schema anddyna_for the name of the CQL map collection. -
Use type text for the map key:
CREATE TABLE my_dynamic_table ( . . . dyna_ map<text, int>, . . . );
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Using CQL, insert data into the map using the base name as a prefix or suffix in the first component of each map pair:
{ prefix_literal : literal, prefix_literal : literal, . . . }The CQL map looks like:
'dyna_' : {dyna_1 : 1, dyna_2 : 2, dyn_3 : 3}DSE Search maps the dynamic field to a map collection column.
