clickhouse: extract more time types as string

hoping clickhouse implicitly converts strings to date/time on insert

flow/connectors/clickhouse/normalize.go

@@ -157,7 +157,7 @@ func (c *ClickhouseConnector) NormalizeRecords(ctx context.Context, req *model.N
 			if err != nil {
 				return nil, fmt.Errorf("error while converting column type to clickhouse type: %w", err)
 			}
-			if clickhouseType == "DateTime64(6)" {
+			if clickhouseType == "DateTime64(6)" || clickhouseType == "Date" || clickhouseType == "TIMESTAMP" {
 				clickhouseType = "String"
 			}
 
@@ -166,7 +166,7 @@ func (c *ClickhouseConnector) NormalizeRecords(ctx context.Context, req *model.N
 
 		// add _peerdb_sign as _peerdb_record_type / 2
 		projection.WriteString(fmt.Sprintf("intDiv(_peerdb_record_type, 2) AS `%s`,", signColName))
-		colSelector.WriteString(fmt.Sprintf("%s,", signColName))
+		colSelector.WriteString(fmt.Sprintf("`%s`,", signColName))
 
 		// add _peerdb_timestamp as _peerdb_version
 		projection.WriteString(fmt.Sprintf("_peerdb_timestamp AS `%s`", versionColName))