Page 2 - Elasticsearch

Since Elastic's license change in January 2021 and the subsequent fork into OpenSearch, both search engines have been evolving technically and legally in different directions. This article puts the fork's history into context, shows the concrete feature divergence, and provides criteria for a well founded migration decision between Elasticsearch and OpenSearch.

Elasticsearch's standard analyzer treats every language the same and thereby ignores word stems, stopwords and special characters that differ completely between German, French or English. A custom analyzer per language, combined with a per-field-per-language mapping strategy, turns a generic full text search into one that actually returns the right hits in every shop language.

Magento stores search synonyms per store view in a dedicated database table and translates them into an Elasticsearch synonym filter during index building. Anyone who does not understand this mechanism ends up maintaining synonyms that never take effect, either because a reindex is missing or because they hit the wrong store view. This article walks through the complete path from the admin interface to the analyzer configuration inside the Elasticsearch index.

A technically correct search that still shows the wrong products first costs revenue without ever showing up in an error log. Tuning search relevance in Magento 2 means understanding the underlying multi_match query, weighting attributes deliberately, and letting business signals such as sales figures and stock levels actively shape ranking.

Runtime fields compute a field at query time with a Painless script, instead of storing it fixed in the mapping at index time. That lets you try out new analytics ideas immediately, without reindexing billions of documents before knowing whether the idea is even worthwhile.

Index aliases are more than an alternate name for an index: used strategically they become the central versioning tool that permanently decouples clients from physical index names. Between filtered aliases for multi-tenancy, routing aliases for shard optimization and the write index flag for controlled rollovers, an architecture emerges where indices can be swapped out without a single application ever touching its configuration.

Since the license change of Elasticsearch and Kibana in January 2021, OpenSearch Dashboards and Kibana have grown into two separate projects. For Magento operators who want to visualize search analytics, layered navigation breakdowns, or reindex monitoring, that raises the question of which tool is the better long-term foundation.

As soon as a Symfony application serves more than one language, the question comes up of how that should be reflected in the URL structure. The built-in {_locale} routing parameter covers the basic case, but it's not enough once the paths themselves also need translating, for example /de/produkte versus /en/products. Planning this structure cleanly from the start saves painful refactoring later and avoids SEO problems caused by missing or incorrect hreflang tags.

The Visual Merchandiser is a Commerce feature, but category merchandising rules can be technically rebuilt in Magento Open Source as well. Coupling product order to stock level, margin and sales figures requires understanding position values, plugin points on the product collection, and the effect on the catalog index.

Pure BM25 scoring only knows text relevance, no business goals. The Function Score Query closes this gap by combining the textual score with additional factors such as sales figures, stock level, or freshness. Anyone who masters field_value_factor and decay functions can steer search results deliberately by business logic without sacrificing textual relevance.