Merge pull request #11731 from XiaoyuMSFT/rcsibranch

Rcsibranch

Author: PRMerger9

docs/relational-databases/stored-procedures/specify-parameters.md

@@ -77,6 +77,9 @@ GO
 
 > [!NOTE]  
 >  If the default value is a character string that contains embedded blanks or punctuation, or if it starts with a number (for example, 6xxx), it must be enclosed in single, straight quotation marks.  
+
+> [!NOTE] 
+> Default parameters are not supported in Azure SQL Data Warehouse or Parallel Data Warehouse. 
   
  If no value can be specified appropriately as a default for the parameter, specify NULL as the default. It is a good idea to have the procedure return a customized message if the procedure is executed without a value for the parameter.  
 

docs/t-sql/statements/alter-database-transact-sql-set-options.md

@@ -2907,6 +2907,7 @@ SET
 <option_spec>::=
 {
 <RESULT_SET_CACHING>
+|<snapshot_option>
 }
 ;
 
@@ -2915,6 +2916,12 @@ SET
 RESULT_SET_CACHING {ON | OFF}
 }
 
+<snapshot_option>::=
+{
+READ_COMMITTED_SNAPSHOT {ON | OFF }
+}
+
+
 ```
 
 ## Arguments
@@ -2924,7 +2931,7 @@ RESULT_SET_CACHING {ON | OFF}
 Is the name of the database to be modified.
 
 <a name="result_set_caching"></a> RESULT_SET_CACHING { ON | OFF }   
-Applies to Azure SQL Data Warehouse (preview)
+**Applies to** Azure SQL Data Warehouse (preview)
 
 This command must be run while connected to the `master` database.  Change to this database setting takes effect immediately.  Storage costs are incurred by caching query result sets. After disabling result caching for a database, previously persisted result cache will immediately be deleted from Azure SQL Data Warehouse storage. A new column, is_result_set_caching_on, is introduced in `sys.databases` to show the result cache setting for a database.  
 
@@ -2942,6 +2949,23 @@ Specifies that query result sets returned from this database will not be cached
 command|Like|%DWResultCacheDb%|
 | | |
 
+
+<a name="snapshot_option"></a> READ_COMMITTED_SNAPSHOT  { ON | OFF }   
+**Applies to** Azure SQL Data Warehouse (preview)
+
+ON
+Enables the READ_COMMITTED_SNAPSHOT option at the database level.
+
+OFF
+Turn off READ_COMMITTED_SNAPSHOT option at the database level.
+
+Turning READ_COMMITTED_SNAPSHOT ON or OFF for a database will kill all open connections to this database.  You may want to make this change during database maintenance window or wait until there is no active connection to the database except for the connection executing the ALTER DATABSE command.  The database does not have to be in single-user mode.  Changing READ_COMMITTED_SNAPSHOT setting at session level is not supported.  To verify this setting for a database, check  is_read_committed_snapshot_on column in sys.databases.
+
+In a database with READ_COMMITTED_SNAPSHOT enabled, queries may experience slower performance due to the scan of versions if multiple data versions are present. Long open transactions can also cause increase in the size of the database if there are data changes by these transactions which blocks the cleanup of versions.  
+
+
+
+
 ## Remarks
 
 Cached result set is reused for a query if all of the following requirements are all met:
@@ -2954,12 +2978,9 @@ Once result set caching is turned ON for a database, results are cached for all
 
 ## Permissions
 
-Requires these permissions:
+To set RESULT_SET_CACHING option, a user needs server-level principal login (the one created by the provisioning process) or be a member of the `dbmanager` database role.  
 
-- Server-level principal login (the one created by the provisioning process), or
-- Member of the `dbmanager` database role.
-
-The owner of the database cannot alter the database unless the owner is a member of the dbmanager role.
+To set READ_COMMITTED_SNAPSHOT option, a user needs ALTER permission on the database.
 
 ## Examples
 
@@ -3024,6 +3045,12 @@ FROM sys.dm_pdw_request_steps
 WHERE command like '%DWResultCacheDb%' and step_index = 0;
 ```
 
+### Enable Read_Committed_Snapshot option for a database
+```sql
+ALTER DATABASE MyDatabase  
+SET READ_COMMITTED_SNAPSHOT ON
+```
+
 ## See also
 
 - [DATABASEPROPERTYEX](../../t-sql/functions/databasepropertyex-transact-sql.md)

docs/t-sql/statements/create-materialized-view-as-select-transact-sql.md

@@ -90,7 +90,7 @@ When MIN/MAX aggregates are used in the SELECT list of materialized view definit
 
 - FOR_APPEND is required.  For example:
   ```sql 
-  CREATE MATRIALIZED VIEW mv_test2  
+  CREATE MATERIALIZED VIEW mv_test2  
   WITH (distribution = hash(i_category_id), FOR_APPEND)  
   AS
   SELECT MAX(i.i_rec_start_date) as max_i_rec_start_date, MIN(i.i_rec_end_date) as min_i_rec_end_date, i.i_item_sk, i.i_item_id, i.i_category_id