Add ES feature compatibility tables (VARIANT, search function)

Add VARIANT vs Dynamic Mapping and search() vs query_string comparison
tables to ES migration docs (EN + ZH-CN), sourced from feature
comparison document.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: dataroaring

docs/migration/elasticsearch-to-doris.md

@@ -93,6 +93,43 @@ Doris's [Inverted Index](../table-design/index/inverted-index/overview.md) provi
 | `{"bool": {"should": [...]}}` | `WHERE ... OR ...` |
 | `{"exists": {"field": "email"}}` | `WHERE email IS NOT NULL` |
 
+## Feature Compatibility
+
+### VARIANT Type vs ES Dynamic Mapping
+
+Doris [VARIANT](../data-operate/import/complex-types/variant.md) type provides comparable functionality to Elasticsearch Dynamic Mapping for flexible schema handling.
+
+| Feature | Doris VARIANT | ES Dynamic Mapping | Status |
+|---------|--------------|-------------------|--------|
+| Dynamic schema inference | Auto-infer JSON field types | Dynamic Mapping | Compatible |
+| Predefined field types | `MATCH_NAME 'field': type` | Explicit Mapping | Compatible |
+| Pattern-based type matching | `MATCH_NAME_GLOB 'pattern*': type` | dynamic_templates | Compatible |
+| Field index configuration | `INDEX ... PROPERTIES("field_pattern"=...)` | Mapping + Index Settings | Compatible |
+| Custom analyzer | `CREATE INVERTED INDEX ANALYZER` | Custom Analyzer | Compatible |
+| Sub-column count limit | `variant_max_subcolumns_count` | `mapping.total_fields.limit` | Compatible |
+| Sparse column optimization | `variant_enable_typed_paths_to_sparse` | N/A | Doris-specific |
+| Nested array objects | Flattened handling | Nested Type | Partial |
+
+### Search Function vs ES Query String
+
+Doris `search()` function provides Lucene-compatible query string syntax similar to Elasticsearch `query_string`.
+
+| Feature | Doris search() | ES query_string | Status |
+|---------|---------------|----------------|--------|
+| Query string syntax | Lucene mode | query_string query | Compatible |
+| Multi-field search | `fields` parameter | multi_match / fields | Supported |
+| best_fields mode | Supported | Supported | Supported |
+| cross_fields mode | Supported | Supported | Supported |
+| VARIANT sub-column search | `variant.field:term` | Object/Nested search | Supported |
+| Boolean queries | AND/OR/NOT | AND/OR/NOT | Supported |
+| Phrase queries | `"exact phrase"` | `"exact phrase"` | Supported |
+| Wildcards | `*`, `?` | `*`, `?` | Supported |
+| Regular expressions | `/pattern/` | `/pattern/` | Supported |
+| Relevance scoring | Disabled | BM25 | Not supported |
+| Fuzzy queries | Not supported | `term~2` | Not supported |
+| Range queries | Not supported | `[a TO z]` | Not supported |
+| Proximity queries | Not supported | `"foo bar"~5` | Not supported |
+
 ## Next Steps
 
 - [Inverted Index](../table-design/index/inverted-index/overview.md) - Full-text search in Doris

i18n/zh-CN/docusaurus-plugin-content-docs/current/migration/elasticsearch-to-doris.md

@@ -93,6 +93,43 @@ Doris 的[倒排索引](../table-design/index/inverted-index/overview.md)提供
 | `{"bool": {"should": [...]}}` | `WHERE ... OR ...` |
 | `{"exists": {"field": "email"}}` | `WHERE email IS NOT NULL` |
 
+## 功能兼容性
+
+### VARIANT 类型与 ES Dynamic Mapping 对比
+
+Doris [VARIANT](../data-operate/import/complex-types/variant.md) 类型提供与 Elasticsearch Dynamic Mapping 相当的灵活 Schema 处理功能。
+
+| 功能 | Doris VARIANT | ES Dynamic Mapping | 状态 |
+|------|--------------|-------------------|------|
+| 动态 Schema 推断 | 自动推断 JSON 字段类型 | Dynamic Mapping | 对齐 |
+| 预定义字段类型 | `MATCH_NAME 'field': type` | Explicit Mapping | 对齐 |
+| 模式匹配指定类型 | `MATCH_NAME_GLOB 'pattern*': type` | dynamic_templates | 对齐 |
+| 字段索引配置 | `INDEX ... PROPERTIES("field_pattern"=...)` | Mapping + Index Settings | 对齐 |
+| 自定义分析器 | `CREATE INVERTED INDEX ANALYZER` | Custom Analyzer | 对齐 |
+| 子列数量限制 | `variant_max_subcolumns_count` | `mapping.total_fields.limit` | 对齐 |
+| 稀疏列优化 | `variant_enable_typed_paths_to_sparse` | N/A | Doris 特有 |
+| Nested 数组对象 | 扁平化处理 | Nested Type | 部分支持 |
+
+### Search 函数与 ES Query String 对比
+
+Doris `search()` 函数提供与 Elasticsearch `query_string` 兼容的 Lucene 查询字符串语法。
+
+| 功能 | Doris search() | ES query_string | 状态 |
+|------|---------------|----------------|------|
+| Query String 语法 | Lucene mode | query_string query | 兼容 |
+| 多字段搜索 | `fields` 参数 | multi_match / fields | 支持 |
+| best_fields 模式 | 支持 | 支持 | 支持 |
+| cross_fields 模式 | 支持 | 支持 | 支持 |
+| VARIANT 子列搜索 | `variant.field:term` | Object/Nested 搜索 | 支持 |
+| 布尔查询 | AND/OR/NOT | AND/OR/NOT | 支持 |
+| 短语查询 | `"exact phrase"` | `"exact phrase"` | 支持 |
+| 通配符 | `*`, `?` | `*`, `?` | 支持 |
+| 正则表达式 | `/pattern/` | `/pattern/` | 支持 |
+| 评分排序 | 已禁用 | BM25 | 不支持 |
+| 模糊查询 | 不支持 | `term~2` | 不支持 |
+| 范围查询 | 不支持 | `[a TO z]` | 不支持 |
+| 近似查询 | 不支持 | `"foo bar"~5` | 不支持 |
+
 ## 下一步
 
 - [倒排索引](../table-design/index/inverted-index/overview.md) - Doris 中的全文搜索