FullText Indexes
The SB-Tree index algorithm provides support for FullText indexes. These indexes allow you to index text as a single word and its radix. FullText indexes are like having a search engine on your database.
NOTE: Bear in mind that there is a difference between
FULLTEXT
without theLUCENE
operator, which uses a FullText index with the SB-Tree index algorithm andFULLTEXT
with theLUCENE
operator, which uses a FullText index through the Lucene Engine.For more information on the latter, see Lucene FullText Index.
Creating FullText Indexes
If you want to create an index using the FullText SB-Tree index algorithm, you can do so using the CREATE INDEX
command.
orientdb> CREATE INDEX City.name ON City(name) FULLTEXT
This creates a FullText index on the property name
of the class City
, using the default configuration.
FullText Index Parameters
In the event that the default FullText Index configuration is not sufficient to your needs, there are a number of parameters available to fine tune how it generates the index.
Parameter | Default | Description |
---|---|---|
indexRadix |
TRUE |
Word prefixes will be also index |
ignoreChars |
" |
Chars to skip when indexing |
separatorChars |
\r\n\t:;,.|+*/\=!?[](.md) |
|
minWordLength |
3 |
Minimum word length to index |
stopWords |
the in a at as and or for his her him this that what which while up with be was were is |
Stop words escluded from indexing |
To configure a FullText Index, from version 1.7 on, you can do so through the OrientDB console or the Java API. When configuring the index from the console, use the CREATE INDEX
command with the METADATA
operator.
orientdb> CREATE INDEX City.name ON City(name) FULLTEXT METADATA
{"indexRadix": true, "ignoreChars": "&", "separatorChars": " |()",
"minWordLength": 4, "stopWords": ["the", "of"]}
Alternatively, you can configure the index in Java.
OClass city = db.getClass("City");
ODocument metadata = new ODocument();
metadata.field("indexRadix", true);
metadata.field("stopWords", Arrays.asList(new String[] { "the", "in", "a", "at" }));
metadata.field("separatorChars", " :;?[](.md)");
metadata.field("ignoreChars", "$&");
metadata.field("minWordLength", 5);
city.createIndex("City.name", "FULLTEXT", null, metadata, null, new String[] { "name" });