- const INDEX_TYPE_TEXT = 0;
- const INDEX_TYPE_KEYWORD = 1;
- const INDEX_TYPE_INTEGER = 2;
- const INDEX_TYPE_NUMBER = 3;
- const INDEX_TYPE_DATETIME = 4;
- const INDEX_TYPE_NESTED = 5;
- const INDEX_TYPE_BOOL = 6;
+ /**
+ * TEXT fields are suitable for natural language and may be subject to
+ * analysis such as stemming.
+ *
+ * Read more:
+ * https://wikimediafoundation.org/2018/08/07/anatomy-search-token-affection/
+ * https://wikimediafoundation.org/2018/09/13/anatomy-search-variation-under-nature/
+ */
+ const INDEX_TYPE_TEXT = 'text';
+ /**
+ * KEYWORD fields are indexed without any processing, so are appropriate
+ * for e.g. URLs. The content will often consist of a single token.
+ */
+ const INDEX_TYPE_KEYWORD = 'keyword';
+ const INDEX_TYPE_INTEGER = 'integer';
+ const INDEX_TYPE_NUMBER = 'number';
+ const INDEX_TYPE_DATETIME = 'datetime';
+ const INDEX_TYPE_NESTED = 'nested';
+ const INDEX_TYPE_BOOL = 'bool';