Change collate and ctype fields to type text

This changes the data type of the catalog fields datcollate, datctype,
collcollate, and collctype from name to text.  There wasn't ever a
really good reason for them to be of type name; presumably this was
just carried over from when they were fixed-size fields in pg_control,
first into the corresponding pg_database fields, and then to
pg_collation.  The values are not identifiers or object names, and we
don't ever look them up that way.

Changing to type text saves space in the typical case, since locale
names are typically only a few bytes long.  But it is also possible
that an ICU locale name with several customization options appended
could be longer than 63 bytes, so this also enables that case, which
was previously probably broken.

Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/5e756dd6-0e91-d778-96fd-b1bcb06c161a@2ndquadrant.com

1 files changed, 19 insertions, 10 deletions

diff --git a/src/backend/utils/adt/pg_locale.c b/src/backend/utils/adt/pg_locale.c
index 33cccc5c6c7..aefa0818d0a 100644
--- a/src/backend/utils/adt/pg_locale.c
+++ b/src/backend/utils/adt/pg_locale.c
@@ -179,7 +179,7 @@ pg_perm_setlocale(int category, const char *locale)
 	 */
 	if (category == LC_CTYPE)
 	{
-		static char save_lc_ctype[NAMEDATALEN + 20];
+		static char save_lc_ctype[LOCALE_NAME_BUFLEN];
 
 		/* copy setlocale() return value before callee invokes it again */
 		strlcpy(save_lc_ctype, result, sizeof(save_lc_ctype));
@@ -1288,17 +1288,21 @@ lookup_collation_cache(Oid collation, bool set_flags)
 	{
 		/* Attempt to set the flags */
 		HeapTuple	tp;
-		Form_pg_collation collform;
+		Datum		datum;
+		bool		isnull;
 		const char *collcollate;
 		const char *collctype;
 
 		tp = SearchSysCache1(COLLOID, ObjectIdGetDatum(collation));
 		if (!HeapTupleIsValid(tp))
 			elog(ERROR, "cache lookup failed for collation %u", collation);
-		collform = (Form_pg_collation) GETSTRUCT(tp);
 
-		collcollate = NameStr(collform->collcollate);
-		collctype = NameStr(collform->collctype);
+		datum = SysCacheGetAttr(COLLOID, tp, Anum_pg_collation_collcollate, &isnull);
+		Assert(!isnull);
+		collcollate = TextDatumGetCString(datum);
+		datum = SysCacheGetAttr(COLLOID, tp, Anum_pg_collation_collctype, &isnull);
+		Assert(!isnull);
+		collctype = TextDatumGetCString(datum);
 
 		cache_entry->collate_is_c = ((strcmp(collcollate, "C") == 0) ||
 									 (strcmp(collcollate, "POSIX") == 0));
@@ -1484,7 +1488,7 @@ pg_newlocale_from_collation(Oid collid)
 		const char *collctype pg_attribute_unused();
 		struct pg_locale_struct result;
 		pg_locale_t resultp;
-		Datum		collversion;
+		Datum		datum;
 		bool		isnull;
 
 		tp = SearchSysCache1(COLLOID, ObjectIdGetDatum(collid));
@@ -1492,8 +1496,12 @@ pg_newlocale_from_collation(Oid collid)
 			elog(ERROR, "cache lookup failed for collation %u", collid);
 		collform = (Form_pg_collation) GETSTRUCT(tp);
 
-		collcollate = NameStr(collform->collcollate);
-		collctype = NameStr(collform->collctype);
+		datum = SysCacheGetAttr(COLLOID, tp, Anum_pg_collation_collcollate, &isnull);
+		Assert(!isnull);
+		collcollate = TextDatumGetCString(datum);
+		datum = SysCacheGetAttr(COLLOID, tp, Anum_pg_collation_collctype, &isnull);
+		Assert(!isnull);
+		collctype = TextDatumGetCString(datum);
 
 		/* We'll fill in the result struct locally before allocating memory */
 		memset(&result, 0, sizeof(result));
@@ -1587,13 +1595,15 @@ pg_newlocale_from_collation(Oid collid)
 #endif							/* not USE_ICU */
 		}
 
-		collversion = SysCacheGetAttr(COLLOID, tp, Anum_pg_collation_collversion,
+		datum = SysCacheGetAttr(COLLOID, tp, Anum_pg_collation_collversion,
 									  &isnull);
 		if (!isnull)
 		{
 			char	   *actual_versionstr;
 			char	   *collversionstr;
 
+			collversionstr = TextDatumGetCString(datum);
+
 			actual_versionstr = get_collation_actual_version(collform->collprovider, collcollate);
 			if (!actual_versionstr)
 			{
@@ -1606,7 +1616,6 @@ pg_newlocale_from_collation(Oid collid)
 						(errmsg("collation \"%s\" has no actual version, but a version was specified",
 								NameStr(collform->collname))));
 			}
-			collversionstr = TextDatumGetCString(collversion);
 
 			if (strcmp(actual_versionstr, collversionstr) != 0)
 				ereport(WARNING,