Fix timeInterval for mysql datasource (#8651)

* Fix timeInterval for mysql datasource

This changes the > to >= and the < to <=, so the intervals are inclusive.
This should fix the #8635

* Fix validation

pkg/tsdb/mysql/macros.go

@@ -73,7 +73,7 @@ func (m *MySqlMacroEngine) EvaluateMacro(name string, args []string) (string, er
 		if len(args) == 0 {
 			return "", fmt.Errorf("missing time column argument for macro %v", name)
 		}
-		return fmt.Sprintf("%s > FROM_UNIXTIME(%d) AND %s < FROM_UNIXTIME(%d)", args[0], uint64(m.TimeRange.GetFromAsMsEpoch()/1000), args[0], uint64(m.TimeRange.GetToAsMsEpoch()/1000)), nil
+		return fmt.Sprintf("%s >= FROM_UNIXTIME(%d) AND %s <= FROM_UNIXTIME(%d)", args[0], uint64(m.TimeRange.GetFromAsMsEpoch()/1000), args[0], uint64(m.TimeRange.GetToAsMsEpoch()/1000)), nil
 	default:
 		return "", fmt.Errorf("Unknown macro %v", name)
 	}

pkg/tsdb/mysql/macros_test.go

@@ -36,7 +36,7 @@ func TestMacroEngine(t *testing.T) {
 			sql, err := engine.Interpolate("WHERE $__timeFilter(time_column)")
 			So(err, ShouldBeNil)
 
-			So(sql, ShouldEqual, "WHERE time_column > FROM_UNIXTIME(18446744066914186738) AND time_column < FROM_UNIXTIME(18446744066914187038)")
+			So(sql, ShouldEqual, "WHERE time_column >= FROM_UNIXTIME(18446744066914186738) AND time_column <= FROM_UNIXTIME(18446744066914187038)")
 		})
 
 	})

public/app/plugins/datasource/mysql/partials/query.editor.html

@@ -46,7 +46,7 @@ Table:
 
 Macros:
 - $__time(column) -> UNIX_TIMESTAMP(column) as time_sec
-- $__timeFilter(column) ->  UNIX_TIMESTAMP(time_date_time) > from AND UNIX_TIMESTAMP(time_date_time) < 1492750877
+- $__timeFilter(column) ->  UNIX_TIMESTAMP(time_date_time) ≥ from AND UNIX_TIMESTAMP(time_date_time) ≤ 1492750877
 		</pre>
 	</div>