Merge pull request #281 from JuliaMongo/DOCSP-8163

(DOCSP-8163) and (DOCSP-12999) Add new default limits to the system variables table, and clean up the table

Author: JuliaMongo

source/includes/fact-system-vars.rst

@@ -18,22 +18,20 @@ Overview
 |bi-short| provides the following environment variables:
 
 .. list-table::
-   :widths: 30 10 40 10 10
+   :widths: 30 10 40 40
    :stub-columns: 1
    :header-rows: 1
 
    * - System Variable
      - Data Type
      - Description
-     - Default Value (Atlas-hosted)
-     - Default Value (On Premises)
+     - Default Value
    * - ``full_pushdown_exec_mode``
      - boolean
      - Specifies whether a query error is returned for queries with
        clauses that aren't fully translated to the MongoDB query language.
        SQL query predicates are used to filter data returned by the query.
      - ``0 (false)``
-     - ``0 (false)``
    * - ``log_level``
      - integer
      - Specifies the logging level for |bi-short|:
@@ -43,27 +41,39 @@ Overview
          ``mongosqld`` events and state changes.
        - ``1``: Log messages for database users and ``mongosqld`` administrators.
        - ``2``: For internal use only.
-     - ``2``
-     - ``0``
+     - ``2 (Atlas-hosted) and 0 (on premises)``
    * - ``max_nested_table_depth``
      - integer
      - Specifies the maximum number of unique nested field paths that
        ``mongosqld`` maps to a relational table for a collection.
      - ``50``
-     - ``50``
-   * - ``max_num_columns_per_table``
+   * - ``max_num_global_tables``
+     - integer
+     - The maximum number of tables allowed in a MongoDB deployment with an automatically-
+       generated schema.
+     - ``4000``
+   * - ``max_num_tables_per_collection``
+     - integer
+     - The maximum number of tables allowed in a collection in a table with an
+       automatically-generated schema.
+     - ``200``
+   * - ``max_nested_table_depth``
+     - integer
+     - The default limit for table's nesting depth of arrays
+       that MongoDB translates to tables, in a collection with an 
+       automatically-generated schema.
+     - ``10``
+   * - ``max_num_fields_per_collection``
      - integer
-     - The maximum number of unique fields that ``mongosqld`` maps to
-       relational columns for a collection.
-     - ``1000``
-     - ``1000``
+     - The maximum number of fields examined per collection in a table with an
+       automatically-generated schema.
+     - ``2000``
    * - ``mongodb_max_varchar_length``
      - integer
      - Specifies the maximum string length returned for columns using
        the ``VARCHAR`` data type. A value of ``0`` specifies
        no limit.
      - ``0``
-     - ``0``
    * - ``polymorphic_type_conversion_mode``
      - string
      - Determines how |bi-short| evaluates document fields that are
@@ -91,7 +101,18 @@ Overview
          discovered during sampling, even if the fields do not appear
          as multiple data types.
      -  ``off``
-     -  ``off``
+   * - ``reconcile_arithmetic_agg_functions``
+     - boolean
+     - Allows you to choose the behavior where MongoDB does not
+       automatically convert types for some queries using arithmetic
+       aggregate functions. In MongoDB version 3.6 and earlier, this
+       behavior results in improved performance, compared with implicit
+       type conversions for arithmetic aggregation functions in subsequent
+       versions.
+
+       See :doc:`Type Conversion Modes </reference/type-conversion>` for
+       more information.
+     - ``true``
    * - ``sample_refresh_interval_secs``
      - integer
      - Specifies how frequently, in seconds, that the |bi-short| schema
@@ -101,7 +122,6 @@ Overview
        See :doc:`Cached Sampling </schema/cached-sampling>` for more
        information.
      - ``0``
-     - ``0``
    * - ``sample_size``
      - integer
      - Specifies how many documents |bi-short| samples when generating
@@ -111,7 +131,6 @@ Overview
        See :doc:`Cached Sampling </schema/cached-sampling>` for more
        information.
      - ``100``
-     - ``100``
    * - ``schema_mapping_mode``
      - string
      - Specifies how the MongoDB schema is transformed into a relational
@@ -123,7 +142,6 @@ Overview
          a field occuring in a sample.
 
      - ``lattice``
-     - ``lattice``
    * - ``type_conversion_mode``
      - string
      - Specifies the semantics that |bi-short| uses for type conversions,
@@ -132,7 +150,6 @@ Overview
        - ``mysql``
        - ``mongosql``
      - ``mongosql``
-     - ``mongosql``
 
 Setting System Variables
 ------------------------