From 420067a7e138ea60ed316c3a0938275c14ee1d98 Mon Sep 17 00:00:00 2001
From: Andreas Christou <andreas.christou@grafana.com>
Date: Wed, 17 Apr 2024 22:49:51 +0100
Subject: [PATCH] MSSQL: Add `SQL_VARIANT` converter and update test (#85823)

Add SQL_VARIANT converter and update test
---
 pkg/tsdb/mssql/mssql.go      | 15 +++++++++++++++
 pkg/tsdb/mssql/mssql_test.go |  4 +++-
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/pkg/tsdb/mssql/mssql.go b/pkg/tsdb/mssql/mssql.go
index 8d1cd05c98c..b0d31e2a70c 100644
--- a/pkg/tsdb/mssql/mssql.go
+++ b/pkg/tsdb/mssql/mssql.go
@@ -403,5 +403,20 @@ func (t *mssqlQueryResultTransformer) GetConverterList() []sqlutil.StringConvert
 				},
 			},
 		},
+		{
+			Name:           "handle SQL_VARIANT",
+			InputScanKind:  reflect.Pointer,
+			InputTypeName:  "SQL_VARIANT",
+			ConversionFunc: func(in *string) (*string, error) { return in, nil },
+			Replacer: &sqlutil.StringFieldReplacer{
+				OutputFieldType: data.FieldTypeNullableString,
+				ReplaceFunc: func(in *string) (any, error) {
+					if in == nil {
+						return nil, nil
+					}
+					return in, nil
+				},
+			},
+		},
 	}
 }
diff --git a/pkg/tsdb/mssql/mssql_test.go b/pkg/tsdb/mssql/mssql_test.go
index 7030e14e3a2..40c6ee50ac3 100644
--- a/pkg/tsdb/mssql/mssql_test.go
+++ b/pkg/tsdb/mssql/mssql_test.go
@@ -92,6 +92,7 @@ func TestMSSQL(t *testing.T) {
 						c_datetimeoffset datetimeoffset,
 
 						c_uuid uniqueidentifier
+						c_sql_variant sql_variant
 					)
 				`
 
@@ -114,7 +115,7 @@ func TestMSSQL(t *testing.T) {
 					'char10', 'varchar10', 'text',
 					N'☺nchar12☺', N'☺nvarchar12☺', N'☺text☺',
 					CAST('%s' AS DATETIME), CAST('%s' AS DATETIME2), CAST('%s' AS SMALLDATETIME), CAST('%s' AS DATE), CAST('%s' AS TIME), SWITCHOFFSET(CAST('%s' AS DATETIMEOFFSET), '-07:00'),
-					CONVERT(uniqueidentifier, '%s')
+					CONVERT(uniqueidentifier, '%s'), 'test-sql-variant'
 		`, d, d2, d, d, d, d2, uuid)
 
 		_, err = db.Exec(sql)
@@ -170,6 +171,7 @@ func TestMSSQL(t *testing.T) {
 			require.Equal(t, dt2.In(time.FixedZone("UTC-7", int(-7*60*60))).Unix(), (*frames[0].Fields[22].At(0).(*time.Time)).Unix())
 
 			require.Equal(t, uuid, *frames[0].Fields[23].At(0).(*string))
+			require.Equal(t, "test-sql-variant", *frames[0].Fields[24].At(0).(*string))
 		})
 	})