From ec497a5ad6a0849efa3fb2fd05988bd8e0c0865d Mon Sep 17 00:00:00 2001
From: Simon Riggs <simon@2ndQuadrant.com>
Date: Tue, 22 Mar 2011 23:10:35 +0000
Subject: [PATCH] Make FKs valid at creation when added as column constraints.

Bug report from Alvaro Herrera
---
 src/backend/commands/tablecmds.c   | 2 +-
 src/backend/nodes/copyfuncs.c      | 1 +
 src/backend/nodes/equalfuncs.c     | 1 +
 src/backend/nodes/outfuncs.c       | 1 +
 src/backend/parser/gram.y          | 3 +++
 src/backend/parser/parse_utilcmd.c | 1 +
 src/include/nodes/parsenodes.h     | 1 +
 7 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index f677a8e8bd..596cd86401 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -5595,7 +5595,7 @@ ATAddForeignKeyConstraint(AlteredTableInfo *tab, Relation rel,
 									  CONSTRAINT_FOREIGN,
 									  fkconstraint->deferrable,
 									  fkconstraint->initdeferred,
-									  !fkconstraint->skip_validation,
+									  fkconstraint->initially_valid,
 									  RelationGetRelid(rel),
 									  fkattnum,
 									  numfks,
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index b903e457a0..0eac9826a4 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -2341,6 +2341,7 @@ _copyConstraint(Constraint *from)
 	COPY_SCALAR_FIELD(fk_upd_action);
 	COPY_SCALAR_FIELD(fk_del_action);
 	COPY_SCALAR_FIELD(skip_validation);
+	COPY_SCALAR_FIELD(initially_valid);
 
 	return newnode;
 }
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index 10b160f537..c811077563 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -2270,6 +2270,7 @@ _equalConstraint(Constraint *a, Constraint *b)
 	COMPARE_SCALAR_FIELD(fk_upd_action);
 	COMPARE_SCALAR_FIELD(fk_del_action);
 	COMPARE_SCALAR_FIELD(skip_validation);
+	COMPARE_SCALAR_FIELD(initially_valid);
 
 	return true;
 }
diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c
index 46435ab21c..47f3523366 100644
--- a/src/backend/nodes/outfuncs.c
+++ b/src/backend/nodes/outfuncs.c
@@ -2625,6 +2625,7 @@ _outConstraint(StringInfo str, Constraint *node)
 			WRITE_CHAR_FIELD(fk_upd_action);
 			WRITE_CHAR_FIELD(fk_del_action);
 			WRITE_BOOL_FIELD(skip_validation);
+			WRITE_BOOL_FIELD(initially_valid);
 			break;
 
 		case CONSTR_ATTR_DEFERRABLE:
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 7c94aadf3b..27fdccae5b 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -2621,6 +2621,7 @@ ColConstraintElem:
 					n->fk_upd_action	= (char) ($5 >> 8);
 					n->fk_del_action	= (char) ($5 & 0xFF);
 					n->skip_validation  = FALSE;
+					n->initially_valid  = true;
 					$$ = (Node *)n;
 				}
 		;
@@ -2820,6 +2821,7 @@ ConstraintElem:
 					n->deferrable		= ($11 & 1) != 0;
 					n->initdeferred		= ($11 & 2) != 0;
 					n->skip_validation  = false;
+					n->initially_valid  = true;
 					$$ = (Node *)n;
 				}
 			| FOREIGN KEY '(' columnList ')' REFERENCES qualified_name
@@ -2836,6 +2838,7 @@ ConstraintElem:
 					n->fk_upd_action	= (char) ($10 >> 8);
 					n->fk_del_action	= (char) ($10 & 0xFF);
 					n->skip_validation  = true;
+					n->initially_valid  = false;
 					$$ = (Node *)n;
 				}
 		;
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c
index 3dffcded4a..eafc3b3053 100644
--- a/src/backend/parser/parse_utilcmd.c
+++ b/src/backend/parser/parse_utilcmd.c
@@ -1696,6 +1696,7 @@ transformFKConstraints(CreateStmtContext *cxt,
 			Constraint *constraint = (Constraint *) lfirst(fkclist);
 
 			constraint->skip_validation = true;
+			constraint->initially_valid  = true;
 		}
 	}
 
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index b7e7104f44..41fdb3e6ba 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -1536,6 +1536,7 @@ typedef struct Constraint
 	char		fk_upd_action;	/* ON UPDATE action */
 	char		fk_del_action;	/* ON DELETE action */
 	bool		skip_validation;	/* skip validation of existing rows? */
+	bool		initially_valid;	/* start the new constraint as valid */
 } Constraint;
 
 /* ----------------------