Index analyzer and search analyzer could be set separately. From now , index analyzer has been removed in favor of just using the analyzer setting
Previously, index_analyzer and search_analyzer could be set separately, while the analyzer setting would set both. The index_analyzer setting has been removed in favour of just using the analyzer setting.
If just the analyzer is set, it will be used at index time and at search time. To use a different analyzer at search time, specify both the analyzer and a search_analyzer.
The index_analyzer, search_analyzer, and analyzer type-level settings have also been removed, as it is no longer possible to select fields based on the type name.
The _analyzer meta-field, which allowed setting an analyzer per document has also been removed. It will be ignored on older indices.