Add min time interval to mysql and mssql

docs/sources/features/datasources/mssql.md

@@ -33,6 +33,22 @@ Name | Description
 *User* | Database user's login/username
 *Password* | Database user's password
 
+### Min time interval
+A lower limit for the `$__interval` variable. Recommended to be set to write frequency, for example `1m` if your data is written every minute.
+This option can also be overridden/configured in a dashboard panel under data source options. It's important to note that this value **needs** to be formatted as a
+number followed by a valid time identifier, e.g. `1m` (1 minute) or `30s` (30 seconds). The following time identifiers are supported:
+
+Identifier | Description
+------------ | -------------
+`y`   | year
+`M`   | month
+`w`   | week
+`d`   | day
+`h`   | hour
+`m`   | minute
+`s`   | second
+`ms`  | millisecond
+
 ### Database User Permissions (Important!)
 
 The database user you specify when you add the data source should only be granted SELECT permissions on

docs/sources/features/datasources/mysql.md

@@ -36,6 +36,22 @@ Name | Description
 *User* | Database user's login/username
 *Password* | Database user's password
 
+### Min time interval
+A lower limit for the `$__interval` variable. Recommended to be set to write frequency, for example `1m` if your data is written every minute.
+This option can also be overridden/configured in a dashboard panel under data source options. It's important to note that this value **needs** to be formatted as a
+number followed by a valid time identifier, e.g. `1m` (1 minute) or `30s` (30 seconds). The following time identifiers are supported:
+
+Identifier | Description
+------------ | -------------
+`y`   | year
+`M`   | month
+`w`   | week
+`d`   | day
+`h`   | hour
+`m`   | minute
+`s`   | second
+`ms`  | millisecond
+
 ### Database User Permissions (Important!)
 
 The database user you specify when you add the data source should only be granted SELECT permissions on