The FST index supports regex queries on text. Decreases on-disk index by 4-6 times.
- Only supports regex queries
- Only supported on stored or completed Pinot segments (no consuming segments).
- Only supported on dictionary-encoded columns.
- Works better for prefix queries
For more information on the FST construction and code, see Lucene documentation.
To enable the FST index on a dictionary-encoded column, include the following configuration:
"fieldConfigList":[
{
"name":"text_col_1",
"encodingType":"DICTIONARY",
"indexType":"FST"
}
]
The FST index generates one FST index file (.lucene.fst)
. If the inverted index is enabled, this is further able to take advantage of that.
For more information about enabling the FST index, see ways to enable indexes.
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