diff --git a/internal/function_time_parser.go b/internal/function_time_parser.go
index 0becda7..2658f40 100644
--- a/internal/function_time_parser.go
+++ b/internal/function_time_parser.go
@@ -639,8 +639,8 @@ func yearMonthDayParser(text []rune, t *time.Time) (int, error) {
 	if err != nil {
 		return 0, fmt.Errorf("could not parse year number: %s", err)
 	}
-	if len(text) < progress || text[progress] != separator {
-		return 0, fmt.Errorf("could not parse year-month-day: [%c] not found after [%s]", separator, string(text[:progress]))
+	if len(text) <= progress || text[progress] != separator {
+		return 0, fmt.Errorf("could not parse year-month-day: [%c] not found after [%s]", separator, string(text))
 	}
 	progress += 1
 
@@ -649,8 +649,8 @@ func yearMonthDayParser(text []rune, t *time.Time) (int, error) {
 		return 0, fmt.Errorf("could not parse month number: %s", err)
 	}
 	progress += mProgress
-	if len(text) < progress || text[progress] != separator {
-		return 0, fmt.Errorf("could not parse year-month-day: [%c] not found after [%s]", separator, string(text[:progress]))
+	if len(text) <= progress || text[progress] != separator {
+		return 0, fmt.Errorf("could not parse year-month-day: [%c] not found after [%s]", separator, string(text))
 	}
 
 	progress += 1
@@ -895,11 +895,11 @@ func hourMinuteParser(text []rune, t *time.Time) (int, error) {
 	if err != nil {
 		return 0, fmt.Errorf("could not parse hour: %s", err)
 	}
-	if text[hProgress] != ':' {
-		return 0, fmt.Errorf("could not parse hour:minute format: character after hour [%s] is not a `:`", string(text[:hProgress]))
+	if len(text) <= hProgress || text[hProgress] != ':' {
+		return 0, fmt.Errorf("could not parse hour:minute format: character after hour [%s] is not a [:]", string(text))
 	}
 	hProgress += 1
-	mProgress, m, err := parseDigitRespectingOptionalPlaces(text, 0, 59)
+	mProgress, m, err := parseDigitRespectingOptionalPlaces(text[hProgress:], 0, 59)
 	if err != nil {
 		return 0, fmt.Errorf("could not parse minute: %s", err)
 	}
diff --git a/query_test.go b/query_test.go
index 93924e0..a5dd71f 100644
--- a/query_test.go
+++ b/query_test.go
@@ -3785,6 +3785,16 @@ SELECT date, EXTRACT(ISOYEAR FROM date), EXTRACT(YEAR FROM date), EXTRACT(MONTH
 			query:        `SELECT PARSE_DATE("%Y%m%d", "20081225") AS parsed`,
 			expectedRows: [][]interface{}{{"2008-12-25"}},
 		},
+		{
+			name:        "parse date with %F no day field",
+			query:       `SELECT PARSE_DATE("%F", "2008-01") AS parsed`,
+			expectedErr: "could not parse year-month-day: [-] not found after [2008-01]",
+		},
+		{
+			name:        "parse date with %F no month field",
+			query:       `SELECT PARSE_DATE("%F", "2008") AS parsed`,
+			expectedErr: "could not parse year-month-day: [-] not found after [2008]",
+		},
 		{
 			name:         "parse date with %F",
 			query:        `SELECT PARSE_DATE("%F", "2008-12-25") AS parsed`,
@@ -3986,6 +3996,22 @@ SELECT date, EXTRACT(ISOYEAR FROM date), EXTRACT(YEAR FROM date), EXTRACT(MONTH
 			query:        `SELECT TIME_TRUNC(TIME "15:30:00", HOUR)`,
 			expectedRows: [][]interface{}{{"15:00:00"}},
 		},
+		{
+			name:         "parse_time with %R",
+			query:        `SELECT PARSE_TIME("%R", "14:30")`,
+			expectedRows: [][]interface{}{{"14:30:00"}},
+		},
+		{
+			name:        "parse_time with %R without minute element",
+			query:       `SELECT PARSE_TIME("%R", "14")`,
+			expectedErr: "could not parse hour:minute format: character after hour [14] is not a [:]",
+		},
+
+		{
+			name:        "parse_time with %R without separator",
+			query:       `SELECT PARSE_TIME("%R", "14")`,
+			expectedErr: "could not parse hour:minute format: character after hour [14] is not a [:]",
+		},
 		{
 			name:         "format_time with %R",
 			query:        `SELECT FORMAT_TIME("%R", TIME "15:30:00")`,