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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2018-12-19 17:35:12 -0500 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2018-12-19 17:46:25 -0500 |
| commit | 586b98fdf1aaef4a27744f8b988479aad4bd9a01 (patch) | |
| tree | a74687bfd94d9abc9a68c0f076aad66dbe619865 /src/backend/nodes/nodeFuncs.c | |
| parent | 68f6f2b7395fe3e403034bcd97a1fcfbcc68ae10 (diff) | |
| download | postgresql-586b98fdf1aaef4a27744f8b988479aad4bd9a01.tar.gz postgresql-586b98fdf1aaef4a27744f8b988479aad4bd9a01.zip | |
Make type "name" collation-aware.
The "name" comparison operators now all support collations, making them
functionally equivalent to "text" comparisons, except for the different
physical representation of the datatype. They do, in fact, mostly share
the varstr_cmp and varstr_sortsupport infrastructure, which has been
slightly enlarged to handle the case.
To avoid changes in the default behavior of the datatype, set name's
typcollation to C_COLLATION_OID not DEFAULT_COLLATION_OID, so that
by default comparisons to a name value will continue to use strcmp
semantics. (This would have been the case for system catalog columns
anyway, because of commit 6b0faf723, but doing this makes it true for
user-created name columns as well. In particular, this avoids
locale-dependent changes in our regression test results.)
In consequence, tweak a couple of places that made assumptions about
collatable base types always having typcollation DEFAULT_COLLATION_OID.
I have not, however, attempted to relax the restriction that user-
defined collatable types must have that. Hence, "name" doesn't
behave quite like a user-defined type; it acts more like a domain
with COLLATE "C". (Conceivably, if we ever get rid of the need for
catalog name columns to be fixed-length, "name" could actually become
such a domain over text. But that'd be a pretty massive undertaking,
and I'm not volunteering.)
Discussion: https://postgr.es/m/15938.1544377821@sss.pgh.pa.us
Diffstat (limited to 'src/backend/nodes/nodeFuncs.c')
| -rw-r--r-- | src/backend/nodes/nodeFuncs.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/src/backend/nodes/nodeFuncs.c b/src/backend/nodes/nodeFuncs.c index 54b3dcff3ec..a813e387917 100644 --- a/src/backend/nodes/nodeFuncs.c +++ b/src/backend/nodes/nodeFuncs.c @@ -862,7 +862,11 @@ exprCollation(const Node *expr) coll = ((const MinMaxExpr *) expr)->minmaxcollid; break; case T_SQLValueFunction: - coll = InvalidOid; /* all cases return non-collatable types */ + /* Returns either NAME or a non-collatable type */ + if (((const SQLValueFunction *) expr)->type == NAMEOID) + coll = C_COLLATION_OID; + else + coll = InvalidOid; break; case T_XmlExpr: @@ -1075,7 +1079,9 @@ exprSetCollation(Node *expr, Oid collation) ((MinMaxExpr *) expr)->minmaxcollid = collation; break; case T_SQLValueFunction: - Assert(!OidIsValid(collation)); /* no collatable results */ + Assert((((SQLValueFunction *) expr)->type == NAMEOID) ? + (collation == C_COLLATION_OID) : + (collation == InvalidOid)); break; case T_XmlExpr: Assert((((XmlExpr *) expr)->op == IS_XMLSERIALIZE) ? |