diff --git a/go/sql/parser.go b/go/sql/parser.go
index f7333a7..ebb8b38 100644
--- a/go/sql/parser.go
+++ b/go/sql/parser.go
@@ -17,13 +17,19 @@ var (
 	dropColumnRegexp                     = regexp.MustCompile(`(?i)\bdrop\s+(column\s+|)([\S]+)$`)
 	renameTableRegexp                    = regexp.MustCompile(`(?i)\brename\s+(to|as)\s+`)
 	alterTableExplicitSchemaTableRegexps = []*regexp.Regexp{
+		// ALTER TABLE `scm`.`tbl` something
 		regexp.MustCompile(`(?i)\balter\s+table\s+` + "`" + `([^` + "`" + `]+)` + "`" + `[.]` + "`" + `([^` + "`" + `]+)` + "`" + `\s+(.*$)`),
+		// ALTER TABLE `scm`.tbl something
 		regexp.MustCompile(`(?i)\balter\s+table\s+` + "`" + `([^` + "`" + `]+)` + "`" + `[.]([\S]+)\s+(.*$)`),
+		// ALTER TABLE scm.`tbl` something
 		regexp.MustCompile(`(?i)\balter\s+table\s+([\S]+)[.]` + "`" + `([^` + "`" + `]+)` + "`" + `\s+(.*$)`),
+		// ALTER TABLE scm.tbl something
 		regexp.MustCompile(`(?i)\balter\s+table\s+([\S]+)[.]([\S]+)\s+(.*$)`),
 	}
 	alterTableExplicitTableRegexps = []*regexp.Regexp{
+		// ALTER TABLE `tbl` something
 		regexp.MustCompile(`(?i)\balter\s+table\s+` + "`" + `([^` + "`" + `]+)` + "`" + `\s+(.*$)`),
+		// ALTER TABLE tbl something
 		regexp.MustCompile(`(?i)\balter\s+table\s+([\S]+)\s+(.*$)`),
 	}
 )