Updated On 2025/5/28 19:30, Tender Wang wrote:
Peter Eisentraut <pe...@eisentraut.org <mailto:pe...@eisentraut.org>> 于 2025年5月28日周三 19:23写道：On 27.05.25 05:06, Quan Zongliang wrote: > I noticed that the subtype of AlterDomainStmt is directly using > constants in the code. It is not conducive to the maintenance and > reading of the code. Based on the definition of AlterTableType, use > "AD_" as the prefix. Define several macros to replace the original > characters. > The subtype of AlterTableCmd is defined using an enumeration. The > subtypes of AlterDomainStmt are relatively few in number, and the > original definition uses characters. These definitions still use > characters and maintain the values unchanged. If some plugins or tools > are also processing AlterDomainStmt, there will be no errors. You can still make it an enum and assign the currently in use values to the new symbols, like enum AlterDomainType { AD_AlterDefault = 'T', AD_DropNotNull = 'N', ... I would prefer that. +1 -- Thanks, Tender Wang
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 54ad38247aa..3f09f85a480 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -15696,7 +15696,7 @@ ATPostAlterTypeParse(Oid oldId, Oid oldRelId, Oid
refRelId, char *cmd,
{
AlterDomainStmt *stmt = (AlterDomainStmt *) stm;
- if (stmt->subtype == 'C') /* ADD CONSTRAINT */
+ if (stmt->subtype == AD_AddConstraint)
{
Constraint *con = castNode(Constraint,
stmt->def);
AlterTableCmd *cmd = makeNode(AlterTableCmd);
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 0b5652071d1..103021c0947 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -11629,7 +11629,7 @@ AlterDomainStmt:
{
AlterDomainStmt *n =
makeNode(AlterDomainStmt);
- n->subtype = 'T';
+ n->subtype = AD_AlterDefault;
n->typeName = $3;
n->def = $4;
$$ = (Node *) n;
@@ -11639,7 +11639,7 @@ AlterDomainStmt:
{
AlterDomainStmt *n =
makeNode(AlterDomainStmt);
- n->subtype = 'N';
+ n->subtype = AD_DropNotNull;
n->typeName = $3;
$$ = (Node *) n;
}
@@ -11648,7 +11648,7 @@ AlterDomainStmt:
{
AlterDomainStmt *n =
makeNode(AlterDomainStmt);
- n->subtype = 'O';
+ n->subtype = AD_SetNotNull;
n->typeName = $3;
$$ = (Node *) n;
}
@@ -11657,7 +11657,7 @@ AlterDomainStmt:
{
AlterDomainStmt *n =
makeNode(AlterDomainStmt);
- n->subtype = 'C';
+ n->subtype = AD_AddConstraint;
n->typeName = $3;
n->def = $5;
$$ = (Node *) n;
@@ -11667,7 +11667,7 @@ AlterDomainStmt:
{
AlterDomainStmt *n =
makeNode(AlterDomainStmt);
- n->subtype = 'X';
+ n->subtype = AD_DropConstraint;
n->typeName = $3;
n->name = $6;
n->behavior = $7;
@@ -11679,7 +11679,7 @@ AlterDomainStmt:
{
AlterDomainStmt *n =
makeNode(AlterDomainStmt);
- n->subtype = 'X';
+ n->subtype = AD_DropConstraint;
n->typeName = $3;
n->name = $8;
n->behavior = $9;
@@ -11691,7 +11691,7 @@ AlterDomainStmt:
{
AlterDomainStmt *n =
makeNode(AlterDomainStmt);
- n->subtype = 'V';
+ n->subtype = AD_ValidateConstraint;
n->typeName = $3;
n->name = $6;
$$ = (Node *) n;
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index 25fe3d58016..aff8510755f 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -1343,7 +1343,7 @@ ProcessUtilitySlow(ParseState *pstate,
*/
switch (stmt->subtype)
{
- case 'T': /* ALTER DOMAIN
DEFAULT */
+ case AD_AlterDefault:
/*
* Recursively alter
column default for table and,
@@ -1353,30 +1353,30 @@ ProcessUtilitySlow(ParseState *pstate,
AlterDomainDefault(stmt->typeName,
stmt->def);
break;
- case 'N': /* ALTER DOMAIN
DROP NOT NULL */
+ case AD_DropNotNull:
address =
AlterDomainNotNull(stmt->typeName,
false);
break;
- case 'O': /* ALTER DOMAIN
SET NOT NULL */
+ case AD_SetNotNull:
address =
AlterDomainNotNull(stmt->typeName,
true);
break;
- case 'C': /* ADD
CONSTRAINT */
+ case AD_AddConstraint:
address =
AlterDomainAddConstraint(stmt->typeName,
stmt->def,
&secondaryObject);
break;
- case 'X': /* DROP
CONSTRAINT */
+ case AD_DropConstraint:
address =
AlterDomainDropConstraint(stmt->typeName,
stmt->name,
stmt->behavior,
stmt->missing_ok);
break;
- case 'V': /* VALIDATE
CONSTRAINT */
+ case AD_ValidateConstraint:
address =
AlterDomainValidateConstraint(stmt->typeName,
stmt->name);
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index 4610fc61293..27f54e933ca 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -2531,17 +2531,20 @@ typedef struct AlterCollationStmt
* this command.
* ----------------------
*/
+typedef enum AlterDomainType
+{
+ AD_AlterDefault = 'T', /* SET|DROP DEFAULT */
+ AD_DropNotNull = 'N', /* DROP NOT NULL */
+ AD_SetNotNull = 'O', /* SET NOT NULL */
+ AD_AddConstraint = 'C', /* ADD CONSTRAINT */
+ AD_DropConstraint = 'X', /* DROP CONSTRAINT */
+ AD_ValidateConstraint = 'V', /* VALIDATE CONSTRAINT */
+} AlterDomainType;
+
typedef struct AlterDomainStmt
{
NodeTag type;
- char subtype; /*------------
- * T =
alter column default
- * N =
alter column drop not null
- * O =
alter column set not null
- * C = add
constraint
- * X =
drop constraint
- *------------
- */
+ AlterDomainType subtype; /* Type of domain alteration to apply */
List *typeName; /* domain to work on */
char *name; /* column or constraint name to
act on */
Node *def; /* definition of default or
constraint */
