Add HasDefault column metadata

generator/mysql/query_set.go

@@ -18,6 +18,7 @@ func (m mySqlQuerySet) GetTablesMetaData(db *sql.DB, schemaName string, tableTyp
 SELECT
 		t.table_name as "table.name",
 		col.COLUMN_NAME AS "column.Name",
+		col.COLUMN_DEFAULT IS NOT NULL as "column.HasDefault",
 		col.IS_NULLABLE = "YES" AS "column.IsNullable",
 		col.COLUMN_COMMENT AS "column.Comment",
 		COALESCE(pk.IsPrimaryKey, 0) AS "column.IsPrimaryKey",