Support for SSSSS datetime format pattern

SQL Standard 2016 defines SSSSS format pattern for seconds past midnight in
jsonpath .datetime() method and CAST (... FORMAT ...) SQL clause.  In our
datetime parsing engine we currently support it with SSSS name.

This commit adds SSSSS as an alias for SSSS.  Alias is added in favor of
upcoming jsonpath .datetime() method.  But it's also supported in to_date()/
to_timestamp() as positive side effect.

Discussion: https://postgr.es/m/CAPpHfdsZgYEra_PeCLGNoXOWYx6iU-S3wF8aX0ObQUcZU%2B4XTw%40mail.gmail.com
Author: Nikita Glukhov, Alexander Korotkov
Reviewed-by: Anastasia Lubennikova, Peter Eisentraut

4 files changed, 33 insertions, 5 deletions

diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 9a61f276747..2b4fe0cb593 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -6175,7 +6175,7 @@ SELECT regexp_match('abc01234xyz', '(?:(.*?)(\d+)(.*)){1,1}');
         <entry>microsecond (000000-999999)</entry>
        </row>
        <row>
-        <entry><literal>SSSS</literal></entry>
+        <entry><literal>SSSS</literal>, <literal>SSSSS</literal></entry>
         <entry>seconds past midnight (0-86399)</entry>
        </row>
        <row>
diff --git a/src/backend/utils/adt/formatting.c b/src/backend/utils/adt/formatting.c
index c6f992bfc1b..053affa5cec 100644
--- a/src/backend/utils/adt/formatting.c
+++ b/src/backend/utils/adt/formatting.c
@@ -626,6 +626,7 @@ typedef enum
 	DCH_PM,
 	DCH_Q,
 	DCH_RM,
+	DCH_SSSSS,
 	DCH_SSSS,
 	DCH_SS,
 	DCH_TZH,
@@ -678,6 +679,7 @@ typedef enum
 	DCH_pm,
 	DCH_q,
 	DCH_rm,
+	DCH_sssss,
 	DCH_ssss,
 	DCH_ss,
 	DCH_tz,
@@ -787,7 +789,8 @@ static const KeyWord DCH_keywords[] = {
 	{"PM", 2, DCH_PM, false, FROM_CHAR_DATE_NONE},
 	{"Q", 1, DCH_Q, true, FROM_CHAR_DATE_NONE}, /* Q */
 	{"RM", 2, DCH_RM, false, FROM_CHAR_DATE_GREGORIAN}, /* R */
-	{"SSSS", 4, DCH_SSSS, true, FROM_CHAR_DATE_NONE},	/* S */
+	{"SSSSS", 5, DCH_SSSS, true, FROM_CHAR_DATE_NONE},	/* S */
+	{"SSSS", 4, DCH_SSSS, true, FROM_CHAR_DATE_NONE},
 	{"SS", 2, DCH_SS, true, FROM_CHAR_DATE_NONE},
 	{"TZH", 3, DCH_TZH, false, FROM_CHAR_DATE_NONE},	/* T */
 	{"TZM", 3, DCH_TZM, true, FROM_CHAR_DATE_NONE},
@@ -839,7 +842,8 @@ static const KeyWord DCH_keywords[] = {
 	{"pm", 2, DCH_pm, false, FROM_CHAR_DATE_NONE},
 	{"q", 1, DCH_Q, true, FROM_CHAR_DATE_NONE}, /* q */
 	{"rm", 2, DCH_rm, false, FROM_CHAR_DATE_GREGORIAN}, /* r */
-	{"ssss", 4, DCH_SSSS, true, FROM_CHAR_DATE_NONE},	/* s */
+	{"sssss", 5, DCH_SSSS, true, FROM_CHAR_DATE_NONE},	/* s */
+	{"ssss", 4, DCH_SSSS, true, FROM_CHAR_DATE_NONE},
 	{"ss", 2, DCH_SS, true, FROM_CHAR_DATE_NONE},
 	{"tz", 2, DCH_tz, false, FROM_CHAR_DATE_NONE},	/* t */
 	{"us", 2, DCH_US, true, FROM_CHAR_DATE_NONE},	/* u */
@@ -920,10 +924,10 @@ static const int DCH_index[KeyWord_INDEX_SIZE] = {
 	-1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
 	-1, -1, -1, -1, -1, DCH_A_D, DCH_B_C, DCH_CC, DCH_DAY, -1,
 	DCH_FF1, -1, DCH_HH24, DCH_IDDD, DCH_J, -1, -1, DCH_MI, -1, DCH_OF,
-	DCH_P_M, DCH_Q, DCH_RM, DCH_SSSS, DCH_TZH, DCH_US, -1, DCH_WW, -1, DCH_Y_YYY,
+	DCH_P_M, DCH_Q, DCH_RM, DCH_SSSSS, DCH_TZH, DCH_US, -1, DCH_WW, -1, DCH_Y_YYY,
 	-1, -1, -1, -1, -1, -1, -1, DCH_a_d, DCH_b_c, DCH_cc,
 	DCH_day, -1, DCH_ff1, -1, DCH_hh24, DCH_iddd, DCH_j, -1, -1, DCH_mi,
-	-1, -1, DCH_p_m, DCH_q, DCH_rm, DCH_ssss, DCH_tz, DCH_us, -1, DCH_ww,
+	-1, -1, DCH_p_m, DCH_q, DCH_rm, DCH_sssss, DCH_tz, DCH_us, -1, DCH_ww,
 	-1, DCH_y_yyy, -1, -1, -1, -1
 
 	/*---- chars over 126 are skipped ----*/
diff --git a/src/test/regress/expected/horology.out b/src/test/regress/expected/horology.out
index 74ecb7c10e6..6b53876e062 100644
--- a/src/test/regress/expected/horology.out
+++ b/src/test/regress/expected/horology.out
@@ -3077,6 +3077,14 @@ SELECT to_timestamp('2015-02-11 86000', 'YYYY-MM-DD SSSS');  -- ok
 
 SELECT to_timestamp('2015-02-11 86400', 'YYYY-MM-DD SSSS');
 ERROR:  date/time field value out of range: "2015-02-11 86400"
+SELECT to_timestamp('2015-02-11 86000', 'YYYY-MM-DD SSSSS');  -- ok
+         to_timestamp         
+------------------------------
+ Wed Feb 11 23:53:20 2015 PST
+(1 row)
+
+SELECT to_timestamp('2015-02-11 86400', 'YYYY-MM-DD SSSSS');
+ERROR:  date/time field value out of range: "2015-02-11 86400"
 SELECT to_date('2016-13-10', 'YYYY-MM-DD');
 ERROR:  date/time field value out of range: "2016-13-10"
 SELECT to_date('2016-02-30', 'YYYY-MM-DD');
@@ -3140,4 +3148,16 @@ SELECT to_char('2012-12-12 12:00'::timestamptz, 'YYYY-MM-DD HH:MI:SS TZ');
  2012-12-12 12:00:00 -01:30
 (1 row)
 
+SELECT to_char('2012-12-12 12:00'::timestamptz, 'YYYY-MM-DD SSSS');
+     to_char      
+------------------
+ 2012-12-12 43200
+(1 row)
+
+SELECT to_char('2012-12-12 12:00'::timestamptz, 'YYYY-MM-DD SSSSS');
+     to_char      
+------------------
+ 2012-12-12 43200
+(1 row)
+
 RESET TIME ZONE;
diff --git a/src/test/regress/sql/horology.sql b/src/test/regress/sql/horology.sql
index 3c8580397ac..f7a9da1e954 100644
--- a/src/test/regress/sql/horology.sql
+++ b/src/test/regress/sql/horology.sql
@@ -480,6 +480,8 @@ SELECT to_timestamp('2016-02-29 15:50:55', 'YYYY-MM-DD HH24:MI:SS');  -- ok
 SELECT to_timestamp('2015-02-29 15:50:55', 'YYYY-MM-DD HH24:MI:SS');
 SELECT to_timestamp('2015-02-11 86000', 'YYYY-MM-DD SSSS');  -- ok
 SELECT to_timestamp('2015-02-11 86400', 'YYYY-MM-DD SSSS');
+SELECT to_timestamp('2015-02-11 86000', 'YYYY-MM-DD SSSSS');  -- ok
+SELECT to_timestamp('2015-02-11 86400', 'YYYY-MM-DD SSSSS');
 SELECT to_date('2016-13-10', 'YYYY-MM-DD');
 SELECT to_date('2016-02-30', 'YYYY-MM-DD');
 SELECT to_date('2016-02-29', 'YYYY-MM-DD');  -- ok
@@ -503,5 +505,7 @@ SELECT '2012-12-12 12:00'::timestamptz;
 SELECT '2012-12-12 12:00 America/New_York'::timestamptz;
 
 SELECT to_char('2012-12-12 12:00'::timestamptz, 'YYYY-MM-DD HH:MI:SS TZ');
+SELECT to_char('2012-12-12 12:00'::timestamptz, 'YYYY-MM-DD SSSS');
+SELECT to_char('2012-12-12 12:00'::timestamptz, 'YYYY-MM-DD SSSSS');
 
 RESET TIME ZONE;