Open saurabh500 opened 4 days ago
cc @roji @uc-msft @apoorvdeshmukh @deepaksa1 @imasud00 @David-Engel @cheenamalhotra
Adding GetFieldValue(Async)
@Wraith2 System.Text.Json is part of .NET in modern versions, so a package reference is only needed on old TFMs. Even for those old TFMs, a system dependency such as System.Text.Json is generally not a problem.
Yup, it's just missing from the dependencies list in the first post is all.
@Wraith2 oh I see, thanks!
The support for the JSON data type is in preview in Azure SQL DB https://techcommunity.microsoft.com/t5/azure-sql-blog/native-json-type-amp-json-aggregates-are-now-in-private-preview/ba-p/3830753
To enable applications to leverage JSON effectively, the SqlClient driver will require changes as well.
When it comes to the APIs of the JSON support, the fundamental APIs which are foundational are
SqlDbType.Json
enum.SqlJson
.System.Data.SqlDbType
ships with dotnet/runtime, and changes to SqlDbType will be made in the runtime repo. There is an issue open in dotnet/runtime at https://github.com/dotnet/runtime/issues/103925SqlJson
unlike other SqlTypes will ship in Microsoft.Data.SqlClient.Related EF issue at https://github.com/dotnet/efcore/issues/32150
APIs
The APIs that have been identified for modification are
SqlDataReader.GetFieldValue<string>()
-> Returns a JSON string.SqlDataReader.GetFieldValue<JsonDocument>()
-> Returns a System.Text.JsonDocument.SqlDataReader.GetFieldValueAsync<T>()
async equivalents as well.SqlDbType.Json
: This would allow the SqlParameters to be qualified as Json types.SqlDataReader.GetString(int colOrdinal)
: This should return a JSON string.SqlDataReader.GetFieldValue<byte[]>(int colOrdinal)
. The byte[] returned should be usable by Utf8JsonReader to create a JSON reader. This is the high performance scenario in .Net.SqlDataReader.GetStream()
should support a TextStream which can be serialized as a JSON text. We will need to check if the COLTYPE is JSON, then we stream the data according to the payload sent by the server.SqlDataReader.GetFieldType(Int32)
: Returns the ‘type’ for JSONSqlDataReader.GetSqlJson(Int32)
: Returns aSqlJson
that contains the JSON stored within the corresponding field.SqlParameter
will not have any new APIs exposed. The behavior of existing APIs will take, so that they can work withSqlDbType
andSqlJson
type.Since
SqlDbType
enhancement can be added at the earliest to dotnet/runtime 9.0, M.D.S for .Net runtime, will support JSON for dotnet/runtime 9.0 and above only.The support for JSON in
netfx
version of M.D.S is TBD. One of the hurdles is thatSystem.Data.SqlDbType
which is available from System.Data.dll, cannot be enhanced in .Net framework.Backward compat with server without JSON support
Backward compat of new client with old server. What happens when
SqlDbType.Json
/SqlJson
is used with a server, which doesn't have Json support. This is pending discussions.Technical details
0x0D
tdsType
for JSON is planned to be244
Dependencies
SqlDbType
enum update.