Remove support for postfix (right-unary) operators.

This feature has been a thorn in our sides for a long time, causing
many grammatical ambiguity problems.  It doesn't seem worth the
pain to continue to support it, so remove it.

There are some follow-on improvements we can make in the grammar,
but this commit only removes the bare minimum number of productions,
plus assorted backend support code.

Note that pg_dump and psql continue to have full support, since
they may be used against older servers.  However, pg_dump warns
about postfix operators.  There is also a check in pg_upgrade.

Documentation-wise, I (tgl) largely removed the "left unary"
terminology in favor of saying "prefix operator", which is
a more standard and IMO less confusing term.

I included a catversion bump, although no initial catalog data
changes here, to mark the boundary at which oprkind = 'r'
stopped being valid in pg_operator.

Mark Dilger, based on work by myself and Robert Haas;
review by John Naylor

Discussion: https://postgr.es/m/38ca86db-42ab-9b48-2902-337a0d6b8311@2ndquadrant.com
This commit is contained in:
Tom Lane 2020-09-17 19:38:05 -04:00
parent 76f412ab31
commit 1ed6b89563
32 changed files with 279 additions and 339 deletions

View File

@ -2706,7 +2706,6 @@ deparseOpExpr(OpExpr *node, deparse_expr_cxt *context)
HeapTuple tuple;
Form_pg_operator form;
char oprkind;
ListCell *arg;
/* Retrieve information about the operator from system catalog. */
tuple = SearchSysCache1(OPEROID, ObjectIdGetDatum(node->opno));
@ -2716,18 +2715,16 @@ deparseOpExpr(OpExpr *node, deparse_expr_cxt *context)
oprkind = form->oprkind;
/* Sanity check. */
Assert((oprkind == 'r' && list_length(node->args) == 1) ||
(oprkind == 'l' && list_length(node->args) == 1) ||
Assert((oprkind == 'l' && list_length(node->args) == 1) ||
(oprkind == 'b' && list_length(node->args) == 2));
/* Always parenthesize the expression. */
appendStringInfoChar(buf, '(');
/* Deparse left operand. */
if (oprkind == 'r' || oprkind == 'b')
/* Deparse left operand, if any. */
if (oprkind == 'b')
{
arg = list_head(node->args);
deparseExpr(lfirst(arg), context);
deparseExpr(linitial(node->args), context);
appendStringInfoChar(buf, ' ');
}
@ -2735,12 +2732,8 @@ deparseOpExpr(OpExpr *node, deparse_expr_cxt *context)
deparseOperatorName(buf, form);
/* Deparse right operand. */
if (oprkind == 'l' || oprkind == 'b')
{
arg = list_tail(node->args);
appendStringInfoChar(buf, ' ');
deparseExpr(lfirst(arg), context);
}
appendStringInfoChar(buf, ' ');
deparseExpr(llast(node->args), context);
appendStringInfoChar(buf, ')');

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@ -5159,8 +5159,8 @@ SCRAM-SHA-256$<replaceable>&lt;iteration count&gt;</replaceable>:<replaceable>&l
<structfield>oprkind</structfield> <type>char</type>
</para>
<para>
<literal>b</literal> = infix (<quote>both</quote>), <literal>l</literal> = prefix
(<quote>left</quote>), <literal>r</literal> = postfix (<quote>right</quote>)
<literal>b</literal> = infix operator (<quote>both</quote>),
or <literal>l</literal> = prefix operator (<quote>left</quote>)
</para></entry>
</row>
@ -5188,7 +5188,7 @@ SCRAM-SHA-256$<replaceable>&lt;iteration count&gt;</replaceable>:<replaceable>&l
(references <link linkend="catalog-pg-type"><structname>pg_type</structname></link>.<structfield>oid</structfield>)
</para>
<para>
Type of the left operand
Type of the left operand (0 if none)
</para></entry>
</row>
@ -5266,7 +5266,7 @@ SCRAM-SHA-256$<replaceable>&lt;iteration count&gt;</replaceable>:<replaceable>&l
</table>
<para>
Unused column contain zeroes. For example, <structfield>oprleft</structfield>
Unused columns contain zeroes. For example, <structfield>oprleft</structfield>
is zero for a prefix operator.
</para>

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@ -251,7 +251,7 @@ ALTER EXTENSION <replaceable class="parameter">name</replaceable> DROP <replacea
<para>
The data type(s) of the operator's arguments (optionally
schema-qualified). Write <literal>NONE</literal> for the missing argument
of a prefix or postfix operator.
of a prefix operator.
</para>
</listitem>
</varlistentry>

View File

@ -21,13 +21,13 @@ PostgreSQL documentation
<refsynopsisdiv>
<synopsis>
ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</replaceable> | NONE } , { <replaceable>right_type</replaceable> | NONE } )
ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</replaceable> | NONE } , <replaceable>right_type</replaceable> )
OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_ROLE | CURRENT_USER | SESSION_USER }
ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</replaceable> | NONE } , { <replaceable>right_type</replaceable> | NONE } )
ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</replaceable> | NONE } , <replaceable>right_type</replaceable> )
SET SCHEMA <replaceable>new_schema</replaceable>
ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</replaceable> | NONE } , { <replaceable>right_type</replaceable> | NONE } )
ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</replaceable> | NONE } , <replaceable>right_type</replaceable> )
SET ( { RESTRICT = { <replaceable class="parameter">res_proc</replaceable> | NONE }
| JOIN = { <replaceable class="parameter">join_proc</replaceable> | NONE }
} [, ... ] )
@ -79,8 +79,7 @@ ALTER OPERATOR <replaceable>name</replaceable> ( { <replaceable>left_type</repla
<term><replaceable class="parameter">right_type</replaceable></term>
<listitem>
<para>
The data type of the operator's right operand; write
<literal>NONE</literal> if the operator has no right operand.
The data type of the operator's right operand.
</para>
</listitem>
</varlistentry>

View File

@ -141,7 +141,7 @@ ALTER OPERATOR FAMILY <replaceable>name</replaceable> USING <replaceable class="
<para>
In an <literal>OPERATOR</literal> clause,
the operand data type(s) of the operator, or <literal>NONE</literal> to
signify a left-unary or right-unary operator. Unlike the comparable
signify a prefix operator. Unlike the comparable
syntax in <command>CREATE OPERATOR CLASS</command>, the operand data types
must always be specified.
</para>

View File

@ -224,7 +224,7 @@ COMMENT ON
<para>
The data type(s) of the operator's arguments (optionally
schema-qualified). Write <literal>NONE</literal> for the missing argument
of a prefix or postfix operator.
of a prefix operator.
</para>
</listitem>
</varlistentry>

View File

@ -161,7 +161,7 @@ CREATE OPERATOR CLASS <replaceable class="parameter">name</replaceable> [ DEFAUL
<para>
In an <literal>OPERATOR</literal> clause,
the operand data type(s) of the operator, or <literal>NONE</literal> to
signify a left-unary or right-unary operator. The operand data
signify a prefix operator. The operand data
types can be omitted in the normal case where they are the same
as the operator class's data type.
</para>

View File

@ -86,20 +86,9 @@ CREATE OPERATOR <replaceable>name</replaceable> (
</para>
<para>
At least one of <literal>LEFTARG</literal> and <literal>RIGHTARG</literal> must be defined. For
binary operators, both must be defined. For right unary
operators, only <literal>LEFTARG</literal> should be defined, while for left
unary operators only <literal>RIGHTARG</literal> should be defined.
</para>
<note>
<para>
Right unary, also called postfix, operators are deprecated and will be
removed in <productname>PostgreSQL</productname> version 14.
</para>
</note>
<para>
For binary operators, both <literal>LEFTARG</literal> and
<literal>RIGHTARG</literal> must be defined. For prefix operators only
<literal>RIGHTARG</literal> should be defined.
The <replaceable class="parameter">function_name</replaceable>
function must have been previously defined using <command>CREATE
FUNCTION</command> and must be defined to accept the correct number
@ -160,7 +149,7 @@ CREATE OPERATOR <replaceable>name</replaceable> (
<listitem>
<para>
The data type of the operator's left operand, if any.
This option would be omitted for a left-unary operator.
This option would be omitted for a prefix operator.
</para>
</listitem>
</varlistentry>
@ -169,8 +158,7 @@ CREATE OPERATOR <replaceable>name</replaceable> (
<term><replaceable class="parameter">right_type</replaceable></term>
<listitem>
<para>
The data type of the operator's right operand, if any.
This option would be omitted for a right-unary operator.
The data type of the operator's right operand.
</para>
</listitem>
</varlistentry>

View File

@ -21,7 +21,7 @@ PostgreSQL documentation
<refsynopsisdiv>
<synopsis>
DROP OPERATOR [ IF EXISTS ] <replaceable class="parameter">name</replaceable> ( { <replaceable class="parameter">left_type</replaceable> | NONE } , { <replaceable class="parameter">right_type</replaceable> | NONE } ) [, ...] [ CASCADE | RESTRICT ]
DROP OPERATOR [ IF EXISTS ] <replaceable class="parameter">name</replaceable> ( { <replaceable class="parameter">left_type</replaceable> | NONE } , <replaceable class="parameter">right_type</replaceable> ) [, ...] [ CASCADE | RESTRICT ]
</synopsis>
</refsynopsisdiv>
@ -73,8 +73,7 @@ DROP OPERATOR [ IF EXISTS ] <replaceable class="parameter">name</replaceable> (
<term><replaceable class="parameter">right_type</replaceable></term>
<listitem>
<para>
The data type of the operator's right operand; write
<literal>NONE</literal> if the operator has no right operand.
The data type of the operator's right operand.
</para>
</listitem>
</varlistentry>
@ -113,24 +112,17 @@ DROP OPERATOR ^ (integer, integer);
</para>
<para>
Remove the left unary bitwise complement operator
Remove the bitwise-complement prefix operator
<literal>~b</literal> for type <type>bit</type>:
<programlisting>
DROP OPERATOR ~ (none, bit);
</programlisting>
</para>
<para>
Remove the right unary factorial operator <literal>x!</literal>
for type <type>bigint</type>:
<programlisting>
DROP OPERATOR ! (bigint, none);
</programlisting></para>
<para>
Remove multiple operators in one command:
<programlisting>
DROP OPERATOR ~ (none, bit), ! (bigint, none);
DROP OPERATOR ~ (none, bit), ^ (integer, integer);
</programlisting></para>
</refsect1>

View File

@ -836,7 +836,7 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> )
<para>
When working with non-SQL-standard operator names, you will usually
need to separate adjacent operators with spaces to avoid ambiguity.
For example, if you have defined a left unary operator named <literal>@</literal>,
For example, if you have defined a prefix operator named <literal>@</literal>,
you cannot write <literal>X*@Y</literal>; you must write
<literal>X* @Y</literal> to ensure that
<productname>PostgreSQL</productname> reads it as two operator names
@ -1444,11 +1444,10 @@ $1.somecolumn
</indexterm>
<para>
There are three possible syntaxes for an operator invocation:
There are two possible syntaxes for an operator invocation:
<simplelist>
<member><replaceable>expression</replaceable> <replaceable>operator</replaceable> <replaceable>expression</replaceable> (binary infix operator)</member>
<member><replaceable>operator</replaceable> <replaceable>expression</replaceable> (unary prefix operator)</member>
<member><replaceable>expression</replaceable> <replaceable>operator</replaceable> (unary postfix operator)</member>
</simplelist>
where the <replaceable>operator</replaceable> token follows the syntax
rules of <xref linkend="sql-syntax-operators"/>, or is one of the

View File

@ -97,8 +97,8 @@ Operators
<listitem>
<para>
<productname>PostgreSQL</productname> allows expressions with
prefix and postfix unary (one-argument) operators,
as well as binary (two-argument) operators. Like functions, operators can
prefix (one-argument) operators,
as well as infix (two-argument) operators. Like functions, operators can
be overloaded, so the same problem of selecting the right operator
exists.
</para>
@ -266,7 +266,7 @@ create objects. In such situations, cast arguments to force an exact match.
<para>
If one argument of a binary operator invocation is of the <type>unknown</type> type,
then assume it is the same type as the other argument for this check.
Invocations involving two <type>unknown</type> inputs, or a unary operator
Invocations involving two <type>unknown</type> inputs, or a prefix operator
with an <type>unknown</type> input, will never find a match at this step.
</para>
</step>

View File

@ -20,8 +20,8 @@
</para>
<para>
<productname>PostgreSQL</productname> supports left unary, right
unary, and binary operators. Operators can be
<productname>PostgreSQL</productname> supports prefix
and infix operators. Operators can be
overloaded;<indexterm><primary>overloading</primary><secondary>operators</secondary></indexterm>
that is, the same operator name can be used for different operators
that have different numbers and types of operands. When a query is
@ -64,9 +64,9 @@ SELECT (a + b) AS c FROM test_complex;
</para>
<para>
We've shown how to create a binary operator here. To create unary
operators, just omit one of <literal>leftarg</literal> (for left unary) or
<literal>rightarg</literal> (for right unary). The <literal>function</literal>
We've shown how to create a binary operator here. To create a prefix
operator, just omit the <literal>leftarg</literal>.
The <literal>function</literal>
clause and the argument clauses are the only required items in
<command>CREATE OPERATOR</command>. The <literal>commutator</literal>
clause shown in the example is an optional hint to the query
@ -202,7 +202,7 @@ SELECT (a + b) AS c FROM test_complex;
<para>
Unlike commutators, a pair of unary operators could validly be marked
as each other's negators; that would mean (A x) equals NOT (B x)
for all x, or the equivalent for right unary operators.
for all x.
</para>
<para>

View File

@ -1473,8 +1473,7 @@ FunctionIsVisible(Oid funcid)
* Given a possibly-qualified operator name and exact input datatypes,
* look up the operator. Returns InvalidOid if not found.
*
* Pass oprleft = InvalidOid for a prefix op, oprright = InvalidOid for
* a postfix op.
* Pass oprleft = InvalidOid for a prefix op.
*
* If the operator name is not schema-qualified, it is sought in the current
* namespace search path. If the name is schema-qualified and the given
@ -1580,8 +1579,8 @@ OpernameGetOprid(List *names, Oid oprleft, Oid oprright)
* namespace case, we arrange for entries in earlier namespaces to mask
* identical entries in later namespaces.
*
* The returned items always have two args[] entries --- one or the other
* will be InvalidOid for a prefix or postfix oprkind. nargs is 2, too.
* The returned items always have two args[] entries --- the first will be
* InvalidOid for a prefix oprkind. nargs is always 2, too.
*/
FuncCandidateList
OpernameGetCandidates(List *names, char oprkind, bool missing_schema_ok)

View File

@ -245,7 +245,7 @@ OperatorShellMake(const char *operatorName,
values[Anum_pg_operator_oprname - 1] = NameGetDatum(&oname);
values[Anum_pg_operator_oprnamespace - 1] = ObjectIdGetDatum(operatorNamespace);
values[Anum_pg_operator_oprowner - 1] = ObjectIdGetDatum(GetUserId());
values[Anum_pg_operator_oprkind - 1] = CharGetDatum(leftTypeId ? (rightTypeId ? 'b' : 'r') : 'l');
values[Anum_pg_operator_oprkind - 1] = CharGetDatum(leftTypeId ? 'b' : 'l');
values[Anum_pg_operator_oprcanmerge - 1] = BoolGetDatum(false);
values[Anum_pg_operator_oprcanhash - 1] = BoolGetDatum(false);
values[Anum_pg_operator_oprleft - 1] = ObjectIdGetDatum(leftTypeId);
@ -494,7 +494,7 @@ OperatorCreate(const char *operatorName,
values[Anum_pg_operator_oprname - 1] = NameGetDatum(&oname);
values[Anum_pg_operator_oprnamespace - 1] = ObjectIdGetDatum(operatorNamespace);
values[Anum_pg_operator_oprowner - 1] = ObjectIdGetDatum(GetUserId());
values[Anum_pg_operator_oprkind - 1] = CharGetDatum(leftTypeId ? (rightTypeId ? 'b' : 'r') : 'l');
values[Anum_pg_operator_oprkind - 1] = CharGetDatum(leftTypeId ? 'b' : 'l');
values[Anum_pg_operator_oprcanmerge - 1] = BoolGetDatum(canMerge);
values[Anum_pg_operator_oprcanhash - 1] = BoolGetDatum(canHash);
values[Anum_pg_operator_oprleft - 1] = ObjectIdGetDatum(leftTypeId);

View File

@ -168,10 +168,22 @@ DefineOperator(List *names, List *parameters)
if (typeName2)
typeId2 = typenameTypeId(NULL, typeName2);
/*
* If only the right argument is missing, the user is likely trying to
* create a postfix operator, so give them a hint about why that does not
* work. But if both arguments are missing, do not mention postfix
* operators, as the user most likely simply neglected to mention the
* arguments.
*/
if (!OidIsValid(typeId1) && !OidIsValid(typeId2))
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("at least one of leftarg or rightarg must be specified")));
errmsg("operator argument types must be specified")));
if (!OidIsValid(typeId2))
ereport(ERROR,
(errcode(ERRCODE_INVALID_FUNCTION_DEFINITION),
errmsg("operator right argument type must be specified"),
errdetail("Postfix operators are not supported.")));
if (typeName1)
{

View File

@ -394,7 +394,6 @@ print_expr(const Node *expr, const List *rtable)
}
else
{
/* we print prefix and postfix ops the same... */
printf("%s ", ((opname != NULL) ? opname : "(invalid operator)"));
print_expr(get_leftop((const Expr *) e), rtable);
}

View File

@ -741,10 +741,9 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
%nonassoc '<' '>' '=' LESS_EQUALS GREATER_EQUALS NOT_EQUALS
%nonassoc BETWEEN IN_P LIKE ILIKE SIMILAR NOT_LA
%nonassoc ESCAPE /* ESCAPE must be just above LIKE/ILIKE/SIMILAR */
%left POSTFIXOP /* dummy for postfix Op rules */
/*
* To support target_el without AS, we must give IDENT an explicit priority
* between POSTFIXOP and Op. We can safely assign the same priority to
* between ESCAPE and Op. We can safely assign the same priority to
* various unreserved keywords as needed to resolve ambiguities (this can't
* have any bad effects since obviously the keywords will still behave the
* same as if they weren't keywords). We need to do this:
@ -12993,8 +12992,6 @@ a_expr: c_expr { $$ = $1; }
{ $$ = (Node *) makeA_Expr(AEXPR_OP, $2, $1, $3, @2); }
| qual_Op a_expr %prec Op
{ $$ = (Node *) makeA_Expr(AEXPR_OP, $1, NULL, $2, @1); }
| a_expr qual_Op %prec POSTFIXOP
{ $$ = (Node *) makeA_Expr(AEXPR_OP, $2, $1, NULL, @2); }
| a_expr AND a_expr
{ $$ = makeAndExpr($1, $3, @2); }
@ -13408,8 +13405,6 @@ b_expr: c_expr
{ $$ = (Node *) makeA_Expr(AEXPR_OP, $2, $1, $3, @2); }
| qual_Op b_expr %prec Op
{ $$ = (Node *) makeA_Expr(AEXPR_OP, $1, NULL, $2, @1); }
| b_expr qual_Op %prec POSTFIXOP
{ $$ = (Node *) makeA_Expr(AEXPR_OP, $2, $1, NULL, @2); }
| b_expr IS DISTINCT FROM b_expr %prec IS
{
$$ = (Node *) makeSimpleA_Expr(AEXPR_DISTINCT, "=", $1, $5, @2);
@ -14665,11 +14660,7 @@ target_el: a_expr AS ColLabel
}
/*
* We support omitting AS only for column labels that aren't
* any known keyword. There is an ambiguity against postfix
* operators: is "a ! b" an infix expression, or a postfix
* expression and a column label? We prefer to resolve this
* as an infix expression, which we accomplish by assigning
* IDENT a precedence higher than POSTFIXOP.
* any known keyword.
*/
| a_expr IDENT
{

View File

@ -57,7 +57,7 @@ bool Transform_null_equals = false;
#define PREC_GROUP_NOT_LIKE 9 /* NOT LIKE/ILIKE/SIMILAR */
#define PREC_GROUP_NOT_BETWEEN 10 /* NOT BETWEEN */
#define PREC_GROUP_NOT_IN 11 /* NOT IN */
#define PREC_GROUP_POSTFIX_OP 12 /* generic postfix operators */
#define PREC_GROUP_ANY_ALL 12 /* ANY/ALL */
#define PREC_GROUP_INFIX_OP 13 /* generic infix operators */
#define PREC_GROUP_PREFIX_OP 14 /* generic prefix operators */
@ -71,7 +71,7 @@ bool Transform_null_equals = false;
* 4. LIKE ILIKE SIMILAR
* 5. BETWEEN
* 6. IN
* 7. generic postfix Op
* 7. ANY ALL
* 8. generic Op, including <= => <>
* 9. generic prefix Op
* 10. IS tests (NullTest, BooleanTest, etc)
@ -1031,7 +1031,7 @@ transformAExprOpAny(ParseState *pstate, A_Expr *a)
Node *rexpr = a->rexpr;
if (operator_precedence_warning)
emit_precedence_warnings(pstate, PREC_GROUP_POSTFIX_OP,
emit_precedence_warnings(pstate, PREC_GROUP_ANY_ALL,
strVal(llast(a->name)),
lexpr, NULL,
a->location);
@ -1054,7 +1054,7 @@ transformAExprOpAll(ParseState *pstate, A_Expr *a)
Node *rexpr = a->rexpr;
if (operator_precedence_warning)
emit_precedence_warnings(pstate, PREC_GROUP_POSTFIX_OP,
emit_precedence_warnings(pstate, PREC_GROUP_ANY_ALL,
strVal(llast(a->name)),
lexpr, NULL,
a->location);
@ -2019,7 +2019,7 @@ transformSubLink(ParseState *pstate, SubLink *sublink)
sublink->testexpr, NULL,
sublink->location);
else
emit_precedence_warnings(pstate, PREC_GROUP_POSTFIX_OP,
emit_precedence_warnings(pstate, PREC_GROUP_ANY_ALL,
strVal(llast(sublink->operName)),
sublink->testexpr, NULL,
sublink->location);
@ -3244,28 +3244,11 @@ operator_precedence_group(Node *node, const char **nodename)
group = PREC_GROUP_PREFIX_OP;
}
}
else if (aexpr->kind == AEXPR_OP &&
aexpr->lexpr != NULL &&
aexpr->rexpr == NULL)
{
/* postfix operator */
if (list_length(aexpr->name) == 1)
{
*nodename = strVal(linitial(aexpr->name));
group = PREC_GROUP_POSTFIX_OP;
}
else
{
/* schema-qualified operator syntax */
*nodename = "OPERATOR()";
group = PREC_GROUP_POSTFIX_OP;
}
}
else if (aexpr->kind == AEXPR_OP_ANY ||
aexpr->kind == AEXPR_OP_ALL)
{
*nodename = strVal(llast(aexpr->name));
group = PREC_GROUP_POSTFIX_OP;
group = PREC_GROUP_ANY_ALL;
}
else if (aexpr->kind == AEXPR_DISTINCT ||
aexpr->kind == AEXPR_NOT_DISTINCT)
@ -3356,7 +3339,7 @@ operator_precedence_group(Node *node, const char **nodename)
else
{
*nodename = strVal(llast(s->operName));
group = PREC_GROUP_POSTFIX_OP;
group = PREC_GROUP_ANY_ALL;
}
}
}
@ -3432,9 +3415,8 @@ emit_precedence_warnings(ParseState *pstate,
* Complain if left child, which should be same or higher precedence
* according to current rules, used to be lower precedence.
*
* Exception to precedence rules: if left child is IN or NOT IN or a
* postfix operator, the grouping is syntactically forced regardless of
* precedence.
* Exception to precedence rules: if left child is IN or NOT IN the
* grouping is syntactically forced regardless of precedence.
*/
cgroup = operator_precedence_group(lchild, &copname);
if (cgroup > 0)
@ -3442,7 +3424,7 @@ emit_precedence_warnings(ParseState *pstate,
if (oldprecedence_l[cgroup] < oldprecedence_r[opgroup] &&
cgroup != PREC_GROUP_IN &&
cgroup != PREC_GROUP_NOT_IN &&
cgroup != PREC_GROUP_POSTFIX_OP &&
cgroup != PREC_GROUP_ANY_ALL &&
cgroup != PREC_GROUP_POSTFIX_IS)
ereport(WARNING,
(errmsg("operator precedence change: %s is now lower precedence than %s",

View File

@ -52,7 +52,7 @@ typedef struct OprCacheKey
{
char oprname[NAMEDATALEN];
Oid left_arg; /* Left input OID, or 0 if prefix op */
Oid right_arg; /* Right input OID, or 0 if postfix op */
Oid right_arg; /* Right input OID */
Oid search_path[MAX_CACHED_PATH_LEN];
} OprCacheKey;
@ -88,8 +88,7 @@ static void InvalidateOprCacheCallBack(Datum arg, int cacheid, uint32 hashvalue)
* Given a possibly-qualified operator name and exact input datatypes,
* look up the operator.
*
* Pass oprleft = InvalidOid for a prefix op, oprright = InvalidOid for
* a postfix op.
* Pass oprleft = InvalidOid for a prefix op.
*
* If the operator name is not schema-qualified, it is sought in the current
* namespace search path.
@ -115,10 +114,16 @@ LookupOperName(ParseState *pstate, List *opername, Oid oprleft, Oid oprright,
if (!OidIsValid(oprleft))
oprkind = 'l';
else if (!OidIsValid(oprright))
oprkind = 'r';
else
else if (OidIsValid(oprright))
oprkind = 'b';
else
{
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("postfix operators are not supported"),
parser_errposition(pstate, location)));
oprkind = 0; /* keep compiler quiet */
}
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_FUNCTION),
@ -507,85 +512,6 @@ compatible_oper_opid(List *op, Oid arg1, Oid arg2, bool noError)
}
/* right_oper() -- search for a unary right operator (postfix operator)
* Given operator name and type of arg, return oper struct.
*
* IMPORTANT: the returned operator (if any) is only promised to be
* coercion-compatible with the input datatype. Do not use this if
* you need an exact- or binary-compatible match.
*
* If no matching operator found, return NULL if noError is true,
* raise an error if it is false. pstate and location are used only to report
* the error position; pass NULL/-1 if not available.
*
* NOTE: on success, the returned object is a syscache entry. The caller
* must ReleaseSysCache() the entry when done with it.
*/
Operator
right_oper(ParseState *pstate, List *op, Oid arg, bool noError, int location)
{
Oid operOid;
OprCacheKey key;
bool key_ok;
FuncDetailCode fdresult = FUNCDETAIL_NOTFOUND;
HeapTuple tup = NULL;
/*
* Try to find the mapping in the lookaside cache.
*/
key_ok = make_oper_cache_key(pstate, &key, op, arg, InvalidOid, location);
if (key_ok)
{
operOid = find_oper_cache_entry(&key);
if (OidIsValid(operOid))
{
tup = SearchSysCache1(OPEROID, ObjectIdGetDatum(operOid));
if (HeapTupleIsValid(tup))
return (Operator) tup;
}
}
/*
* First try for an "exact" match.
*/
operOid = OpernameGetOprid(op, arg, InvalidOid);
if (!OidIsValid(operOid))
{
/*
* Otherwise, search for the most suitable candidate.
*/
FuncCandidateList clist;
/* Get postfix operators of given name */
clist = OpernameGetCandidates(op, 'r', false);
/* No operators found? Then fail... */
if (clist != NULL)
{
/*
* We must run oper_select_candidate even if only one candidate,
* otherwise we may falsely return a non-type-compatible operator.
*/
fdresult = oper_select_candidate(1, &arg, clist, &operOid);
}
}
if (OidIsValid(operOid))
tup = SearchSysCache1(OPEROID, ObjectIdGetDatum(operOid));
if (HeapTupleIsValid(tup))
{
if (key_ok)
make_oper_cache_entry(&key, operOid);
}
else if (!noError)
op_error(pstate, op, 'r', arg, InvalidOid, fdresult, location);
return (Operator) tup;
}
/* left_oper() -- search for a unary left operator (prefix operator)
* Given operator name and type of arg, return oper struct.
*
@ -696,8 +622,7 @@ op_signature_string(List *op, char oprkind, Oid arg1, Oid arg2)
appendStringInfoString(&argbuf, NameListToString(op));
if (oprkind != 'r')
appendStringInfo(&argbuf, " %s", format_type_be(arg2));
appendStringInfo(&argbuf, " %s", format_type_be(arg2));
return argbuf.data; /* return palloc'd string buffer */
}
@ -758,17 +683,16 @@ make_op(ParseState *pstate, List *opname, Node *ltree, Node *rtree,
Oid rettype;
OpExpr *result;
/* Select the operator */
/* Check it's not a postfix operator */
if (rtree == NULL)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("postfix operators are not supported")));
/* Select the operator */
if (ltree == NULL)
{
/* right operator */
ltypeId = exprType(ltree);
rtypeId = InvalidOid;
tup = right_oper(pstate, opname, ltypeId, false, location);
}
else if (ltree == NULL)
{
/* left operator */
/* prefix operator */
rtypeId = exprType(rtree);
ltypeId = InvalidOid;
tup = left_oper(pstate, opname, rtypeId, false, location);
@ -795,17 +719,9 @@ make_op(ParseState *pstate, List *opname, Node *ltree, Node *rtree,
parser_errposition(pstate, location)));
/* Do typecasting and build the expression tree */
if (rtree == NULL)
if (ltree == NULL)
{
/* right operator */
args = list_make1(ltree);
actual_arg_types[0] = ltypeId;
declared_arg_types[0] = opform->oprleft;
nargs = 1;
}
else if (ltree == NULL)
{
/* left operator */
/* prefix operator */
args = list_make1(rtree);
actual_arg_types[0] = rtypeId;
declared_arg_types[0] = opform->oprright;

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@ -9198,35 +9198,14 @@ get_oper_expr(OpExpr *expr, deparse_context *context)
}
else
{
/* unary operator --- but which side? */
/* prefix operator */
Node *arg = (Node *) linitial(args);
HeapTuple tp;
Form_pg_operator optup;
tp = SearchSysCache1(OPEROID, ObjectIdGetDatum(opno));
if (!HeapTupleIsValid(tp))
elog(ERROR, "cache lookup failed for operator %u", opno);
optup = (Form_pg_operator) GETSTRUCT(tp);
switch (optup->oprkind)
{
case 'l':
appendStringInfo(buf, "%s ",
generate_operator_name(opno,
InvalidOid,
exprType(arg)));
get_rule_expr_paren(arg, context, true, (Node *) expr);
break;
case 'r':
get_rule_expr_paren(arg, context, true, (Node *) expr);
appendStringInfo(buf, " %s",
generate_operator_name(opno,
exprType(arg),
InvalidOid));
break;
default:
elog(ERROR, "bogus oprkind: %d", optup->oprkind);
}
ReleaseSysCache(tp);
appendStringInfo(buf, "%s ",
generate_operator_name(opno,
InvalidOid,
exprType(arg)));
get_rule_expr_paren(arg, context, true, (Node *) expr);
}
if (!PRETTY_PAREN(context))
appendStringInfoChar(buf, ')');
@ -11087,10 +11066,6 @@ generate_operator_name(Oid operid, Oid arg1, Oid arg2)
p_result = left_oper(NULL, list_make1(makeString(oprname)), arg2,
true, -1);
break;
case 'r':
p_result = right_oper(NULL, list_make1(makeString(oprname)), arg1,
true, -1);
break;
default:
elog(ERROR, "unrecognized oprkind: %d", operform->oprkind);
p_result = NULL; /* keep compiler quiet */

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@ -12650,6 +12650,11 @@ dumpOpr(Archive *fout, OprInfo *oprinfo)
oprcanmerge = PQgetvalue(res, 0, i_oprcanmerge);
oprcanhash = PQgetvalue(res, 0, i_oprcanhash);
/* In PG14 upwards postfix operator support does not exist anymore. */
if (strcmp(oprkind, "r") == 0)
pg_log_warning("postfix operators are not supported anymore (operator \"%s\")",
oprcode);
oprregproc = convertRegProcReference(fout, oprcode);
if (oprregproc)
{
@ -12662,7 +12667,8 @@ dumpOpr(Archive *fout, OprInfo *oprinfo)
/*
* right unary means there's a left arg and left unary means there's a
* right arg
* right arg. (Although the "r" case is dead code for PG14 and later,
* continue to support it in case we're dumping from an old server.)
*/
if (strcmp(oprkind, "r") == 0 ||
strcmp(oprkind, "b") == 0)

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@ -22,6 +22,7 @@ static void check_is_install_user(ClusterInfo *cluster);
static void check_proper_datallowconn(ClusterInfo *cluster);
static void check_for_prepared_transactions(ClusterInfo *cluster);
static void check_for_isn_and_int8_passing_mismatch(ClusterInfo *cluster);
static void check_for_user_defined_postfix_ops(ClusterInfo *cluster);
static void check_for_tables_with_oids(ClusterInfo *cluster);
static void check_for_reg_data_type_usage(ClusterInfo *cluster);
static void check_for_jsonb_9_4_usage(ClusterInfo *cluster);
@ -100,6 +101,13 @@ check_and_dump_old_cluster(bool live_check)
check_for_reg_data_type_usage(&old_cluster);
check_for_isn_and_int8_passing_mismatch(&old_cluster);
/*
* Pre-PG 14 allowed user defined postfix operators, which are not
* supported anymore. Verify there are none, iff applicable.
*/
if (GET_MAJOR_VERSION(old_cluster.major_version) <= 1300)
check_for_user_defined_postfix_ops(&old_cluster);
/*
* Pre-PG 12 allowed tables to be declared WITH OIDS, which is not
* supported anymore. Verify there are none, iff applicable.
@ -896,6 +904,104 @@ check_for_isn_and_int8_passing_mismatch(ClusterInfo *cluster)
check_ok();
}
/*
* Verify that no user defined postfix operators exist.
*/
static void
check_for_user_defined_postfix_ops(ClusterInfo *cluster)
{
int dbnum;
FILE *script = NULL;
bool found = false;
char output_path[MAXPGPATH];
prep_status("Checking for user-defined postfix operators");
snprintf(output_path, sizeof(output_path),
"postfix_ops.txt");
/* Find any user defined postfix operators */
for (dbnum = 0; dbnum < cluster->dbarr.ndbs; dbnum++)
{
PGresult *res;
bool db_used = false;
int ntups;
int rowno;
int i_oproid,
i_oprnsp,
i_oprname,
i_typnsp,
i_typname;
DbInfo *active_db = &cluster->dbarr.dbs[dbnum];
PGconn *conn = connectToServer(cluster, active_db->db_name);
/*
* The query below hardcodes FirstNormalObjectId as 16384 rather than
* interpolating that C #define into the query because, if that
* #define is ever changed, the cutoff we want to use is the value
* used by pre-version 14 servers, not that of some future version.
*/
res = executeQueryOrDie(conn,
"SELECT o.oid AS oproid, "
" n.nspname AS oprnsp, "
" o.oprname, "
" tn.nspname AS typnsp, "
" t.typname "
"FROM pg_catalog.pg_operator o, "
" pg_catalog.pg_namespace n, "
" pg_catalog.pg_type t, "
" pg_catalog.pg_namespace tn "
"WHERE o.oprnamespace = n.oid AND "
" o.oprleft = t.oid AND "
" t.typnamespace = tn.oid AND "
" o.oprright = 0 AND "
" o.oid >= 16384");
ntups = PQntuples(res);
i_oproid = PQfnumber(res, "oproid");
i_oprnsp = PQfnumber(res, "oprnsp");
i_oprname = PQfnumber(res, "oprname");
i_typnsp = PQfnumber(res, "typnsp");
i_typname = PQfnumber(res, "typname");
for (rowno = 0; rowno < ntups; rowno++)
{
found = true;
if (script == NULL &&
(script = fopen_priv(output_path, "w")) == NULL)
pg_fatal("could not open file \"%s\": %s\n",
output_path, strerror(errno));
if (!db_used)
{
fprintf(script, "In database: %s\n", active_db->db_name);
db_used = true;
}
fprintf(script, " (oid=%s) %s.%s (%s.%s, NONE)\n",
PQgetvalue(res, rowno, i_oproid),
PQgetvalue(res, rowno, i_oprnsp),
PQgetvalue(res, rowno, i_oprname),
PQgetvalue(res, rowno, i_typnsp),
PQgetvalue(res, rowno, i_typname));
}
PQclear(res);
PQfinish(conn);
}
if (script)
fclose(script);
if (found)
{
pg_log(PG_REPORT, "fatal\n");
pg_fatal("Your installation contains user-defined postfix operators, which are not\n"
"supported anymore. Consider dropping the postfix operators and replacing\n"
"them with prefix operators or function calls.\n"
"A list of user-defined postfix operators is in the file:\n"
" %s\n\n", output_path);
}
else
check_ok();
}
/*
* Verify that no tables are declared WITH OIDS.

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@ -799,6 +799,10 @@ describeOperators(const char *pattern, bool verbose, bool showSystem)
* anyway, for now, because (1) third-party modules may still be following
* the old convention, and (2) we'd need to do it anyway when talking to a
* pre-9.1 server.
*
* The support for postfix operators in this query is dead code as of
* Postgres 14, but we need to keep it for as long as we support talking
* to pre-v14 servers.
*/
printfPQExpBuffer(&buf,

View File

@ -53,6 +53,6 @@
*/
/* yyyymmddN */
#define CATALOG_VERSION_NO 202009171
#define CATALOG_VERSION_NO 202009172
#endif

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@ -41,7 +41,7 @@ CATALOG(pg_operator,2617,OperatorRelationId)
/* operator owner */
Oid oprowner BKI_DEFAULT(PGUID);
/* 'l', 'r', or 'b' */
/* 'l' for prefix or 'b' for infix */
char oprkind BKI_DEFAULT(b);
/* can be used in merge join? */
@ -50,10 +50,10 @@ CATALOG(pg_operator,2617,OperatorRelationId)
/* can be used in hash join? */
bool oprcanhash BKI_DEFAULT(f);
/* left arg type, or 0 if 'l' oprkind */
/* left arg type, or 0 if prefix operator */
Oid oprleft BKI_LOOKUP(pg_type);
/* right arg type, or 0 if 'r' oprkind */
/* right arg type */
Oid oprright BKI_LOOKUP(pg_type);
/* result datatype */

View File

@ -31,8 +31,6 @@ extern Oid LookupOperWithArgs(ObjectWithArgs *oper, bool noError);
/* NB: the selected operator may require coercion of the input types! */
extern Operator oper(ParseState *pstate, List *op, Oid arg1, Oid arg2,
bool noError, int location);
extern Operator right_oper(ParseState *pstate, List *op, Oid arg,
bool noError, int location);
extern Operator left_oper(ParseState *pstate, List *op, Oid arg,
bool noError, int location);

View File

@ -15,17 +15,15 @@ CREATE OPERATOR <% (
negator = >=%
);
CREATE OPERATOR @#@ (
rightarg = int8, -- left unary
procedure = factorial
);
CREATE OPERATOR #@# (
leftarg = int8, -- right unary
rightarg = int8, -- prefix
procedure = factorial
);
CREATE OPERATOR #%# (
leftarg = int8, -- right unary
leftarg = int8, -- fail, postfix is no longer supported
procedure = factorial
);
ERROR: operator right argument type must be specified
DETAIL: Postfix operators are not supported.
-- Test operator created above
SELECT point '(1,2)' <% widget '(0,0,3)' AS t,
point '(1,2)' <% widget '(0,0,1)' AS f;
@ -35,11 +33,22 @@ SELECT point '(1,2)' <% widget '(0,0,3)' AS t,
(1 row)
-- Test comments
COMMENT ON OPERATOR ###### (int4, NONE) IS 'bad right unary';
ERROR: operator does not exist: integer ######
-- => is disallowed now
COMMENT ON OPERATOR ###### (NONE, int4) IS 'bad prefix';
ERROR: operator does not exist: ###### integer
COMMENT ON OPERATOR ###### (int4, NONE) IS 'bad postfix';
ERROR: postfix operators are not supported
COMMENT ON OPERATOR ###### (int4, int8) IS 'bad infix';
ERROR: operator does not exist: integer ###### bigint
-- Check that DROP on a nonexistent op behaves sanely, too
DROP OPERATOR ###### (NONE, int4);
ERROR: operator does not exist: ###### integer
DROP OPERATOR ###### (int4, NONE);
ERROR: postfix operators are not supported
DROP OPERATOR ###### (int4, int8);
ERROR: operator does not exist: integer ###### bigint
-- => is disallowed as an operator name now
CREATE OPERATOR => (
leftarg = int8, -- right unary
rightarg = int8,
procedure = factorial
);
ERROR: syntax error at or near "=>"
@ -49,15 +58,20 @@ LINE 1: CREATE OPERATOR => (
-- (=> is tested elsewhere)
-- this is legal because ! is not allowed in sql ops
CREATE OPERATOR !=- (
leftarg = int8, -- right unary
rightarg = int8,
procedure = factorial
);
SELECT 2 !=-;
SELECT !=- 10;
?column?
----------
2
3628800
(1 row)
-- postfix operators don't work anymore
SELECT 10 !=-;
ERROR: syntax error at or near ";"
LINE 1: SELECT 10 !=-;
^
-- make sure lexer returns != as <> even in edge cases
SELECT 2 !=/**/ 1, 2 !=/**/ 2;
?column? | ?column?
@ -127,7 +141,7 @@ GRANT USAGE ON SCHEMA schema_op1 TO PUBLIC;
REVOKE USAGE ON SCHEMA schema_op1 FROM regress_rol_op1;
SET ROLE regress_rol_op1;
CREATE OPERATOR schema_op1.#*# (
leftarg = int8, -- right unary
rightarg = int8,
procedure = factorial
);
ERROR: permission denied for schema schema_op1
@ -167,19 +181,19 @@ CREATE OPERATOR === (
ROLLBACK;
-- Should fail. Invalid attribute
CREATE OPERATOR #@%# (
leftarg = int8, -- right unary
rightarg = int8,
procedure = factorial,
invalid_att = int8
);
WARNING: operator attribute "invalid_att" not recognized
-- Should fail. At least leftarg or rightarg should be mandatorily specified
-- Should fail. At least rightarg should be mandatorily specified
CREATE OPERATOR #@%# (
procedure = factorial
);
ERROR: at least one of leftarg or rightarg must be specified
ERROR: operator argument types must be specified
-- Should fail. Procedure should be mandatorily specified
CREATE OPERATOR #@%# (
leftarg = int8
rightarg = int8
);
ERROR: operator function must be specified
-- Should fail. CREATE OPERATOR requires USAGE on TYPE

View File

@ -1066,7 +1066,7 @@ WHERE condefault AND
-- Look for illegal values in pg_operator fields.
SELECT p1.oid, p1.oprname
FROM pg_operator as p1
WHERE (p1.oprkind != 'b' AND p1.oprkind != 'l' AND p1.oprkind != 'r') OR
WHERE (p1.oprkind != 'b' AND p1.oprkind != 'l') OR
p1.oprresult = 0 OR p1.oprcode = 0;
oid | oprname
-----+---------
@ -1077,8 +1077,7 @@ SELECT p1.oid, p1.oprname
FROM pg_operator as p1
WHERE (p1.oprleft = 0 and p1.oprkind != 'l') OR
(p1.oprleft != 0 and p1.oprkind = 'l') OR
(p1.oprright = 0 and p1.oprkind != 'r') OR
(p1.oprright != 0 and p1.oprkind = 'r');
p1.oprright = 0;
oid | oprname
-----+---------
(0 rows)
@ -1285,18 +1284,6 @@ WHERE p1.oprcode = p2.oid AND
-----+---------+-----+---------
(0 rows)
SELECT p1.oid, p1.oprname, p2.oid, p2.proname
FROM pg_operator AS p1, pg_proc AS p2
WHERE p1.oprcode = p2.oid AND
p1.oprkind = 'r' AND
(p2.pronargs != 1
OR NOT binary_coercible(p2.prorettype, p1.oprresult)
OR NOT binary_coercible(p1.oprleft, p2.proargtypes[0])
OR p1.oprright != 0);
oid | oprname | oid | proname
-----+---------+-----+---------
(0 rows)
-- If the operator is mergejoinable or hashjoinable, its underlying function
-- should not be volatile.
SELECT p1.oid, p1.oprname, p2.oid, p2.proname

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@ -18,17 +18,12 @@ CREATE OPERATOR <% (
);
CREATE OPERATOR @#@ (
rightarg = int8, -- left unary
procedure = factorial
);
CREATE OPERATOR #@# (
leftarg = int8, -- right unary
rightarg = int8, -- prefix
procedure = factorial
);
CREATE OPERATOR #%# (
leftarg = int8, -- right unary
leftarg = int8, -- fail, postfix is no longer supported
procedure = factorial
);
@ -37,11 +32,18 @@ SELECT point '(1,2)' <% widget '(0,0,3)' AS t,
point '(1,2)' <% widget '(0,0,1)' AS f;
-- Test comments
COMMENT ON OPERATOR ###### (int4, NONE) IS 'bad right unary';
COMMENT ON OPERATOR ###### (NONE, int4) IS 'bad prefix';
COMMENT ON OPERATOR ###### (int4, NONE) IS 'bad postfix';
COMMENT ON OPERATOR ###### (int4, int8) IS 'bad infix';
-- => is disallowed now
-- Check that DROP on a nonexistent op behaves sanely, too
DROP OPERATOR ###### (NONE, int4);
DROP OPERATOR ###### (int4, NONE);
DROP OPERATOR ###### (int4, int8);
-- => is disallowed as an operator name now
CREATE OPERATOR => (
leftarg = int8, -- right unary
rightarg = int8,
procedure = factorial
);
@ -50,10 +52,12 @@ CREATE OPERATOR => (
-- this is legal because ! is not allowed in sql ops
CREATE OPERATOR !=- (
leftarg = int8, -- right unary
rightarg = int8,
procedure = factorial
);
SELECT 2 !=-;
SELECT !=- 10;
-- postfix operators don't work anymore
SELECT 10 !=-;
-- make sure lexer returns != as <> even in edge cases
SELECT 2 !=/**/ 1, 2 !=/**/ 2;
SELECT 2 !=-- comment to be removed by psql
@ -84,7 +88,7 @@ GRANT USAGE ON SCHEMA schema_op1 TO PUBLIC;
REVOKE USAGE ON SCHEMA schema_op1 FROM regress_rol_op1;
SET ROLE regress_rol_op1;
CREATE OPERATOR schema_op1.#*# (
leftarg = int8, -- right unary
rightarg = int8,
procedure = factorial
);
ROLLBACK;
@ -128,19 +132,19 @@ ROLLBACK;
-- Should fail. Invalid attribute
CREATE OPERATOR #@%# (
leftarg = int8, -- right unary
rightarg = int8,
procedure = factorial,
invalid_att = int8
);
-- Should fail. At least leftarg or rightarg should be mandatorily specified
-- Should fail. At least rightarg should be mandatorily specified
CREATE OPERATOR #@%# (
procedure = factorial
);
-- Should fail. Procedure should be mandatorily specified
CREATE OPERATOR #@%# (
leftarg = int8
rightarg = int8
);
-- Should fail. CREATE OPERATOR requires USAGE on TYPE

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@ -571,7 +571,7 @@ WHERE condefault AND
SELECT p1.oid, p1.oprname
FROM pg_operator as p1
WHERE (p1.oprkind != 'b' AND p1.oprkind != 'l' AND p1.oprkind != 'r') OR
WHERE (p1.oprkind != 'b' AND p1.oprkind != 'l') OR
p1.oprresult = 0 OR p1.oprcode = 0;
-- Look for missing or unwanted operand types
@ -580,8 +580,7 @@ SELECT p1.oid, p1.oprname
FROM pg_operator as p1
WHERE (p1.oprleft = 0 and p1.oprkind != 'l') OR
(p1.oprleft != 0 and p1.oprkind = 'l') OR
(p1.oprright = 0 and p1.oprkind != 'r') OR
(p1.oprright != 0 and p1.oprkind = 'r');
p1.oprright = 0;
-- Look for conflicting operator definitions (same names and input datatypes).
@ -715,15 +714,6 @@ WHERE p1.oprcode = p2.oid AND
OR NOT binary_coercible(p1.oprright, p2.proargtypes[0])
OR p1.oprleft != 0);
SELECT p1.oid, p1.oprname, p2.oid, p2.proname
FROM pg_operator AS p1, pg_proc AS p2
WHERE p1.oprcode = p2.oid AND
p1.oprkind = 'r' AND
(p2.pronargs != 1
OR NOT binary_coercible(p2.prorettype, p1.oprresult)
OR NOT binary_coercible(p1.oprleft, p2.proargtypes[0])
OR p1.oprright != 0);
-- If the operator is mergejoinable or hashjoinable, its underlying function
-- should not be volatile.

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@ -111,7 +111,7 @@ CREATE FUNCTION complex_add(complex, complex)
LANGUAGE C IMMUTABLE STRICT;
-- we can now define the operator. We show a binary operator here but you
-- can also define unary operators by omitting either of leftarg or rightarg.
-- can also define a prefix operator by omitting the leftarg.
CREATE OPERATOR + (
leftarg = complex,
rightarg = complex,

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@ -96,36 +96,22 @@ SELECT n.nspname, r.rolname, format_type(t.oid, null) as typname
--
-- lists all left unary operators
-- lists all prefix operators
--
SELECT n.nspname, o.oprname AS left_unary,
SELECT n.nspname, o.oprname AS prefix_op,
format_type(right_type.oid, null) AS operand,
format_type(result.oid, null) AS return_type
FROM pg_namespace n, pg_operator o,
pg_type right_type, pg_type result
WHERE o.oprnamespace = n.oid
and o.oprkind = 'l' -- left unary
and o.oprkind = 'l' -- prefix ("left unary")
and o.oprright = right_type.oid
and o.oprresult = result.oid
ORDER BY nspname, operand;
--
-- lists all right unary operators
--
SELECT n.nspname, o.oprname AS right_unary,
format_type(left_type.oid, null) AS operand,
format_type(result.oid, null) AS return_type
FROM pg_namespace n, pg_operator o,
pg_type left_type, pg_type result
WHERE o.oprnamespace = n.oid
and o.oprkind = 'r' -- right unary
and o.oprleft = left_type.oid
and o.oprresult = result.oid
ORDER BY nspname, operand;
--
-- lists all binary operators
-- lists all infix operators
--
SELECT n.nspname, o.oprname AS binary_op,
format_type(left_type.oid, null) AS left_opr,
@ -134,7 +120,7 @@ SELECT n.nspname, o.oprname AS binary_op,
FROM pg_namespace n, pg_operator o, pg_type left_type,
pg_type right_type, pg_type result
WHERE o.oprnamespace = n.oid
and o.oprkind = 'b' -- binary
and o.oprkind = 'b' -- infix ("binary")
and o.oprleft = left_type.oid
and o.oprright = right_type.oid
and o.oprresult = result.oid