Postgres/MySQL/MSSQL: Fix region annotations not displayed correctly (#38936) (#38953)

Fix region annotations not displayed correctly when returning timeend column
as epoch timestamp and by that making sure that the returned data frame field
named timeend is treated as time type.

Fixes #38533

(cherry picked from commit fbdaf56a84)

pkg/tsdb/sqleng/sql_engine.go

@@ -20,6 +20,7 @@ import (
 	"github.com/grafana/grafana/pkg/models"
 	"github.com/grafana/grafana/pkg/plugins"
 	"github.com/grafana/grafana/pkg/tsdb/interval"
+	"github.com/grafana/grafana/pkg/util/errutil"
 	"xorm.io/core"
 	"xorm.io/xorm"
 )
@@ -270,11 +271,9 @@ func (e *dataPlugin) executeQuery(query plugins.DataSubQuery, wg *sync.WaitGroup
 		return
 	}
 
-	if qm.timeIndex != -1 {
-		if err := convertSQLTimeColumnToEpochMS(frame, qm.timeIndex); err != nil {
-			errAppendDebug("db convert time column failed", err, interpolatedQuery)
-			return
-		}
+	if err := convertSQLTimeColumnsToEpochMS(frame, qm); err != nil {
+		errAppendDebug("converting time columns failed", err, interpolatedQuery)
+		return
 	}
 
 	if qm.Format == dataQueryFormatSeries {
@@ -375,6 +374,7 @@ func (e *dataPlugin) newProcessCfg(query plugins.DataSubQuery, queryContext plug
 		columnNames:  columnNames,
 		rows:         rows,
 		timeIndex:    -1,
+		timeEndIndex: -1,
 		metricIndex:  -1,
 		metricPrefix: false,
 		queryContext: queryContext,
@@ -418,6 +418,12 @@ func (e *dataPlugin) newProcessCfg(query plugins.DataSubQuery, queryContext plug
 				break
 			}
 		}
+
+		if qm.Format == dataQueryFormatTable && col == "timeend" {
+			qm.timeEndIndex = i
+			continue
+		}
+
 		switch col {
 		case "metric":
 			qm.metricIndex = i
@@ -456,6 +462,7 @@ type dataQueryModel struct {
 	columnNames       []string
 	columnTypes       []*sql.ColumnType
 	timeIndex         int
+	timeEndIndex      int
 	metricIndex       int
 	rows              *core.Rows
 	metricPrefix      bool
@@ -785,6 +792,22 @@ func convertNullableFloat32ToEpochMS(origin *data.Field, newField *data.Field) {
 	}
 }
 
+func convertSQLTimeColumnsToEpochMS(frame *data.Frame, qm *dataQueryModel) error {
+	if qm.timeIndex != -1 {
+		if err := convertSQLTimeColumnToEpochMS(frame, qm.timeIndex); err != nil {
+			return errutil.Wrap("failed to convert time column", err)
+		}
+	}
+
+	if qm.timeEndIndex != -1 {
+		if err := convertSQLTimeColumnToEpochMS(frame, qm.timeEndIndex); err != nil {
+			return errutil.Wrap("failed to convert timeend column", err)
+		}
+	}
+
+	return nil
+}
+
 // convertSQLTimeColumnToEpochMS converts column named time to unix timestamp in milliseconds
 // to make native datetime types and epoch dates work in annotation and table queries.
 func convertSQLTimeColumnToEpochMS(frame *data.Frame, timeIndex int) error {