Update the setting defaults in sql plugin

Signed-off-by: Lantao Jin <[email protected]>

Author: LantaoJin

_search-plugins/sql/settings.md

@@ -72,18 +72,30 @@ Requests to the `_plugins/_ppl` and `_plugins/_sql` endpoints include index name
 
 Setting | Default | Description
 :--- | :--- | :---
-`plugins.sql.enabled` | True | Change to `false` to disable the `SQL` support in the plugin.
-`plugins.ppl.enabled` | True | Change to `false` to disable the `PPL` support in the plugin.
-`plugins.sql.slowlog` | 2 seconds | Configures the time limit (in seconds) for slow queries. The plugin logs slow queries as `Slow query: elapsed=xxx (ms)` in `opensearch.log`.
-`plugins.sql.cursor.keep_alive` | 1 minute | Configures how long the cursor context is kept open. Cursor contexts are resource-intensive, so we recommend a low value.
+`plugins.sql.enabled` | true | Change to `false` to disable the `SQL` support in the plugin.
+`plugins.ppl.enabled` | true | Change to `false` to disable the `PPL` support in the plugin.
+`plugins.sql.slowlog` | 2 | Configures the time limit (in seconds) for slow queries. The plugin logs slow queries as `Slow query: elapsed=xxx (ms)` in `opensearch.log`.
+`plugins.sql.cursor.keep_alive` | 1m | Configures how long the cursor context is kept open. Cursor contexts are resource-intensive, so we recommend a low value.
 `plugins.query.memory_limit` | 85% | Configures the heap memory usage limit for the circuit breaker of the query engine.
-`plugins.query.size_limit` | 10000 | Sets the default size of index that the query engine fetches from OpenSearch.
+`plugins.query.size_limit` | 10000 | Sets the maximum amount of rows returned from a query execution results.
 `plugins.query.datasources.enabled` | true | Change to `false` to disable support for data sources in the plugin.
 `plugins.query.field_type_tolerance` | true | If `false`, then an array is reduced to the first non-array value at any nesting level. For example, `[[1, 2], [3, 4]]` will be reduced to `1`. If `true`, then the array is preserved. Default is `true`.
+`plugins.query.buckets` | 10000 | Sets how many aggregation buckets will return in a single response. The default value equals to `plugins.query.size_limit`.
 `plugins.calcite.enabled` | true | Enables the Apache Calcite query engine, including advanced SQL and PPL capabilities such as subsearches, joins, and lookup operations.
+`plugins.calcite.pushdown.enabled` | true | Change to `false` to disable the operator pushdown optimization. We recommend using the default value.
+`plugins.calcite.fallback.allowed` | false | Change to `true` to allow fallback to v2 engine.
+`plugins.calcite.pushdown.rowcount.estimation.factor` | 0.9 | The value is a factor to multiply the row count of the table scan to get the estimated row count. We recommend using the default value.
 `plugins.calcite.all_join_types.allowed` | false | Enables performance-sensitive join types, like `RIGHT`, `FULL`, and `CROSS` joins. Change to `true` to allow these join operations.
 `plugins.ppl.syntax.legacy.preferred` | true | Controls certain PPL syntax behaviors, including default argument values. When `false`, uses newer syntax standards.
 `plugins.ppl.values.max.limit` | 0 | Sets the maximum number of unique values that the `VALUES` aggregation function can return. A value of `0` indicates no limit.
+`plugins.ppl.rex.max_match.limit` | 10  | Maximum number of matches to extract in `rex` command.
+`plugins.ppl.subsearch.maxout` | 10000 | Sets the maximum of rows to return from subsearch.
+`plugins.ppl.join.subsearch_maxout` | 50000 | Sets the maximum of rows from subsearch to join against.
+`plugins.ppl.pattern.method` | "simple_pattern" | Sets the default patterns method. Another supported method is "brain".
+`plugins.ppl.pattern.mode` | "label" | Sets the default patterns mode. Another supported mode is "aggregation".
+`plugins.ppl.pattern.max.sample.count` | 10 | Sets the default max sample logs returned per pattern in aggregation mode.
+`plugins.ppl.pattern.buffer.limit` | 100000 | Sets the default size of internal temporary buffer used in "brain" algorithm.
+`plugins.ppl.pattern.show.numbered.token` | false | Change to `true` to turn on numbered token output format.
 
 ## Spark connector settings