float support, quoting, cleanup

flow/connectors/bigquery/merge_stmt_generator.go

@@ -101,26 +101,27 @@ func (m *mergeStmtGenerator) generateFlattenedCTE() string {
 		m.syncBatchID, m.dstTableName)
 }
 
-// This function is to support datatypes like JSON which cannot be compared by BigQuery
+// This function is to support datatypes like JSON which either cannot be partitoned by or compared by BigQuery
 func (m *mergeStmtGenerator) transformedPkeyStrings(forPartition bool) []string {
 	pkeys := make([]string, 0, len(m.normalizedTableSchema.PrimaryKeyColumns))
+	transformations := map[qvalue.QValueKind]string{
+		qvalue.QValueKindJSON:    "TO_JSON_STRING(%s)",
+		qvalue.QValueKindFloat32: "CAST(%s as STRING)",
+		qvalue.QValueKindFloat64: "CAST(%s as STRING)",
+	}
+
 	for _, col := range m.normalizedTableSchema.Columns {
 		if slices.Contains(m.normalizedTableSchema.PrimaryKeyColumns, col.Name) {
 			pkeyCol := col.Name
-			switch qvalue.QValueKind(col.Type) {
-			case qvalue.QValueKindJSON:
-				if forPartition {
-					pkeys = append(pkeys, fmt.Sprintf("TO_JSON_STRING(%s)", m.shortColumn[pkeyCol]))
-				} else {
-					pkeys = append(pkeys, fmt.Sprintf("TO_JSON_STRING(_t.%s)=TO_JSON_STRING(_d.%s)",
-						pkeyCol, m.shortColumn[pkeyCol]))
-				}
-			default:
-				if forPartition {
-					pkeys = append(pkeys, m.shortColumn[pkeyCol])
-				} else {
-					pkeys = append(pkeys, fmt.Sprintf("_t.%s=_d.%s", pkeyCol, m.shortColumn[pkeyCol]))
-				}
+			transformation, exists := transformations[qvalue.QValueKind(col.Type)]
+			if !exists {
+				transformation = "%s"
+			}
+			if forPartition {
+				pkeys = append(pkeys, fmt.Sprintf(transformation, m.shortColumn[pkeyCol]))
+			} else {
+				pkeys = append(pkeys, fmt.Sprintf(transformation+"="+transformation,
+					"_t.`"+pkeyCol+"`", "_d."+m.shortColumn[pkeyCol]))
 			}
 		}
 	}