ALTER CONSTRAINT clause for PK/UK/FK

Author: aafemt

doc/sql.extensions/README.ddl.txt

@@ -666,3 +666,16 @@ DROP PACKAGE BODY [IF EXISTS] <package>
 DROP [GLOBAL] MAPPING [IF EXISTS] <mapping>
 ALTER TABLE <table> DROP [IF EXISTS] <column>
 ALTER TABLE <table> DROP CONSTRAINT [IF EXISTS] <constraint>
+
+2) ALTER CONSTRAINT
+
+ANSI standard compliant ALTER CONSTRAINT clause for ALTER TABLE statement.
+
+ALTER TABLE ALTER CONSTRAINT <constraint name> [NOT] ENFORCED
+
+Supported for UNIQUE, PRIMARY KEY and FOREIGN KEY constraints.
+Primary and unique keys cannot be deactivated if they are referenced by any active foreign key.
+
+The corresponding non-standard ALTER INDEX statement is allowed as well.
+
+ODS 13.2 is required.

src/common/ParserTokens.h

@@ -197,6 +197,7 @@ PARSER_TOKEN(TOK_ENABLE, "ENABLE", true)
 PARSER_TOKEN(TOK_ENCRYPT, "ENCRYPT", true)
 PARSER_TOKEN(TOK_END, "END", false)
 PARSER_TOKEN(TOK_ENGINE, "ENGINE", true)
+PARSER_TOKEN(TOK_ENFORCED, "ENFORCED", true)
 PARSER_TOKEN(TOK_ENTRY_POINT, "ENTRY_POINT", true)
 PARSER_TOKEN(TOK_ESCAPE, "ESCAPE", false)
 PARSER_TOKEN(TOK_EXCEPTION, "EXCEPTION", true)

src/dsql/DdlNodes.epp

@@ -112,6 +112,8 @@ static void updateRdbFields(const TypeClause* type,
 	SSHORT& fieldPrecisionNull, SSHORT& fieldPrecision,
 	SSHORT& collationIdNull, SSHORT& collationId,
 	SSHORT& segmentLengthNull, SSHORT& segmentLength);
+static void modifyIndex(thread_db* tdbb, jrd_tra* transaction,
+	const char* name, bool active);
 
 static const char* const CHECK_CONSTRAINT_EXCEPTION = "check_constraint";
 
@@ -179,6 +181,47 @@ void ExecInSecurityDb::executeInSecurityDb(jrd_tra* localTransaction)
 
 //----------------------
 
+// Activate/deactivate given index
+static void modifyIndex(thread_db* tdbb, jrd_tra* transaction,
+	const char* name, bool active)
+{
+	AutoCacheRequest request(tdbb, drq_m_index, DYN_REQUESTS);
+
+	bool found = false;
+	FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
+		IDX IN RDB$INDICES
+		WITH IDX.RDB$INDEX_NAME EQ name
+	{
+		found = true;
+		MODIFY IDX
+			IDX.RDB$INDEX_INACTIVE.NULL = FALSE;
+			IDX.RDB$INDEX_INACTIVE = active ? FALSE : TRUE;
+		END_MODIFY
+	}
+	END_FOR
+
+	if (!found)
+	{
+		// msg 48: "Index not found"
+		status_exception::raise(Arg::PrivateDyn(48));
+	}
+}
+
+// Check if given index is referenced by active foreign key constraint
+static void checkIndexReferenced(thread_db* tdbb, jrd_tra* transaction, const char* name)
+{
+	AutoCacheRequest fkCheck(tdbb, drq_c_active_fk, DYN_REQUESTS);
+
+	FOR(REQUEST_HANDLE fkCheck TRANSACTION_HANDLE transaction)
+		IDX IN RDB$INDICES
+		WITH IDX.RDB$FOREIGN_KEY EQ name AND
+			 IDX.RDB$INDEX_INACTIVE EQ 0 OR IDX.RDB$INDEX_INACTIVE MISSING
+	{
+		// MSG 408: "Can't deactivate index used by an integrity constraint"
+		status_exception::raise(Arg::Gds(isc_integ_index_deactivate));
+	}
+	END_FOR
+}
 
 // Check temporary table reference rules between given child relation and master
 // relation (owner of given PK/UK index).
@@ -7889,6 +7932,48 @@ void AlterRelationNode::execute(thread_db* tdbb, DsqlCompilerScratch* dsqlScratc
 					break;
 				}
 
+				case Clause::TYPE_ALTER_CONSTRAINT:
+				{
+					executeBeforeTrigger();
+
+					const AlterConstraintClause* clause = static_cast<const AlterConstraintClause*>(i->getObject());
+					AutoCacheRequest request(tdbb, drq_get_constr_type, DYN_REQUESTS);
+					bool found = false;
+
+					FOR(REQUEST_HANDLE request TRANSACTION_HANDLE transaction)
+						RC IN RDB$RELATION_CONSTRAINTS
+						WITH RC.RDB$CONSTRAINT_NAME EQ clause->name.c_str() AND
+							 RC.RDB$RELATION_NAME EQ name.c_str()
+					{
+						found = true;
+						fb_utils::exact_name(RC.RDB$CONSTRAINT_TYPE);
+						if (strcmp(RC.RDB$CONSTRAINT_TYPE, PRIMARY_KEY) == 0 ||
+							strcmp(RC.RDB$CONSTRAINT_TYPE, UNIQUE_CNSTRT) == 0)
+						{
+							// Deactivation of primary/unique key requires check for active foreign keys
+							checkIndexReferenced(tdbb, transaction, RC.RDB$INDEX_NAME);
+						}
+						else if (strcmp(RC.RDB$CONSTRAINT_TYPE, FOREIGN_KEY) == 0)
+						{
+							// Activation of foreign key requires check for active partner which is done on index activation
+							// so there is nothing to do here
+						}
+						else
+							status_exception::raise(Arg::Gds(isc_wish_list) << Arg::Gds(isc_ref_cnstrnt_update));
+
+						modifyIndex(tdbb, transaction, RC.RDB$INDEX_NAME, clause->enforced);
+					}
+					END_FOR
+
+					if (!found)
+					{
+						// msg 130: "CONSTRAINT %s does not exist."
+						status_exception::raise(Arg::PrivateDyn(130) << clause->name);
+					}
+
+					break;
+				}
+
 				case Clause::TYPE_ALTER_SQL_SECURITY:
 				{
 					executeBeforeTrigger();
@@ -10060,6 +10145,8 @@ void AlterIndexNode::execute(thread_db* tdbb, DsqlCompilerScratch* dsqlScratch,
 		executeDdlTrigger(tdbb, dsqlScratch, transaction, DTW_BEFORE, DDL_TRIGGER_ALTER_INDEX,
 			name, NULL);
 
+		checkIndexReferenced(tdbb, transaction, name.c_str());
+
 		MODIFY IDX
 			IDX.RDB$INDEX_INACTIVE.NULL = FALSE;
 			IDX.RDB$INDEX_INACTIVE = active ? FALSE : TRUE;

src/dsql/DdlNodes.h

@@ -1317,6 +1317,7 @@ class RelationNode : public DdlNode
 			TYPE_ALTER_COL_NULL,
 			TYPE_ALTER_COL_POS,
 			TYPE_ALTER_COL_TYPE,
+			TYPE_ALTER_CONSTRAINT,
 			TYPE_DROP_COLUMN,
 			TYPE_DROP_CONSTRAINT,
 			TYPE_ALTER_SQL_SECURITY,
@@ -1509,6 +1510,18 @@ class RelationNode : public DdlNode
 		bool silent = false;
 	};
 
+	struct AlterConstraintClause : public Clause
+	{
+		explicit AlterConstraintClause(MemoryPool& p)
+			: Clause(p, TYPE_ALTER_CONSTRAINT),
+			  name(p)
+		{
+		}
+
+		MetaName name;
+		bool enforced = false;
+	};
+
 	RelationNode(MemoryPool& p, RelationSourceNode* aDsqlNode);
 
 	static bool deleteLocalField(thread_db* tdbb, jrd_tra* transaction,

src/dsql/parse.y

@@ -702,6 +702,7 @@ using namespace Firebird;
 %token <metaNamePtr> ANY_VALUE
 %token <metaNamePtr> BTRIM
 %token <metaNamePtr> CALL
+%token <metaNamePtr> ENFORCED
 %token <metaNamePtr> FORMAT
 %token <metaNamePtr> LTRIM
 %token <metaNamePtr> NAMED_ARG_ASSIGN
@@ -4267,6 +4268,13 @@ alter_op($relationNode)
 			clause->name = *$4;
 			$relationNode->clauses.add(clause);
 		}
+	| ALTER CONSTRAINT symbol_constraint_name constraint_enforcement
+		{
+			RelationNode::AlterConstraintClause* clause = newNode<RelationNode::AlterConstraintClause>();
+			clause->name = *$3;
+			clause->enforced = $4;
+			$relationNode->clauses.add(clause);
+		}
 	| ADD column_def($relationNode)
 	| ADD table_constraint_definition($relationNode)
 	| col_opt alter_column_name POSITION pos_short_integer
@@ -4398,6 +4406,12 @@ alter_column_name
 	: keyword_or_column
 	;
 
+%type <boolVal> constraint_enforcement
+constraint_enforcement
+	: NOT ENFORCED	{ $$ = false; }
+	| ENFORCED		{ $$ = true; }
+	;
+
 // below are reserved words that could be used as column identifiers
 // in the previous versions
 
@@ -9615,6 +9629,7 @@ non_reserved_word
 	| UNICODE_VAL
 	// added in FB 6.0
 	| ANY_VALUE
+	| ENFORCED
 	| FORMAT
 	| OWNER
 	;

src/isql/show.epp

@@ -6193,6 +6193,7 @@ static processing_state show_table(const SCHAR* relation_name, bool isView)
 		ISQL_get_index_segments (collist, sizeof(collist), RELC1.RDB$INDEX_NAME, false);
 		bool isPK = false;
 		bool isUK = false;
+		bool isFK = false;
 
 		if (!strncmp (RELC1.RDB$CONSTRAINT_TYPE, "PRIMARY", 7))
 		{
@@ -6208,6 +6209,7 @@ static processing_state show_table(const SCHAR* relation_name, bool isView)
 		}
 		else if (!strncmp (RELC1.RDB$CONSTRAINT_TYPE, "FOREIGN", 7))
 		{
+			isFK = true;
 			isqlGlob.printf("CONSTRAINT %s:%s", RELC1.RDB$CONSTRAINT_NAME, NEWLINE);
 			isqlGlob.printf("  Foreign key (%s)", collist);
 
@@ -6232,17 +6234,14 @@ static processing_state show_table(const SCHAR* relation_name, bool isView)
 					IUTILS_truncate_term (REFC.RDB$DELETE_RULE, static_cast<USHORT>(strlen(REFC.RDB$DELETE_RULE)));
 					ISQL_ri_action_print (REFC.RDB$DELETE_RULE, " On Delete", false);
 				}
-
-				isqlGlob.printf(NEWLINE);
-
 			END_FOR
 			ON_ERROR
 				ISQL_errmsg (fbStatus);
 				return ps_ERR;
 			END_ERROR;
 		}
 
-		if (isPK || isUK) // Special handling for PRIMARY KEY and UNIQUE constraints.
+		if (isPK || isUK || isFK) // Special handling for RI constraints.
 		{
 			FOR IDX IN RDB$INDICES
 			WITH IDX.RDB$INDEX_NAME = RELC1.RDB$INDEX_NAME
@@ -6260,6 +6259,9 @@ static processing_state show_table(const SCHAR* relation_name, bool isView)
 				if (explicit_index)
 					isqlGlob.printf(" %s", RELC1.RDB$INDEX_NAME);
 
+				if (IDX.RDB$INDEX_INACTIVE == 1)
+					isqlGlob.printf(" Not enforced");
+
 				isqlGlob.prints(NEWLINE);
 			END_FOR
 			ON_ERROR

src/jrd/drq.h

@@ -249,6 +249,8 @@ enum drq_type_t
 	drq_l_pub_rel_name,		// lookup relation by name
 	drq_l_pub_all_rels,		// iterate through all user relations
 	drq_e_pub_tab_all,		// erase relation from all publication
+	drq_get_constr_type,	// get constraint type
+	drq_c_active_fk,		// check if active FK references this index
 
 	drq_MAX
 };

src/jrd/ini.epp

@@ -138,9 +138,6 @@ namespace
 		{ "RDB$TRIGGER_19", (UCHAR) nam_indices,
 			RDB$TRIGGERS.RDB$TRIGGER_TYPE.PRE_ERASE, sizeof(trigger19), trigger19,
 			0, ODS_8_0 },
-		{ "RDB$TRIGGER_20", (UCHAR) nam_indices,
-			RDB$TRIGGERS.RDB$TRIGGER_TYPE.PRE_MODIFY, sizeof(trigger20),
-			trigger20, 0, ODS_8_0 },
 		{ "RDB$TRIGGER_21", (UCHAR) nam_trgs,
 			RDB$TRIGGERS.RDB$TRIGGER_TYPE.PRE_ERASE, sizeof(trigger21), trigger21,
 			0, ODS_8_0 },
@@ -185,9 +182,6 @@ namespace
 		{ "RDB$TRIGGER_23", 1, "cnstrnt_fld_del", ODS_8_0 },
 		{ "RDB$TRIGGER_22", 1, "check_trig_update", ODS_8_0 },
 		{ "RDB$TRIGGER_21", 1, "check_trig_del", ODS_8_0 },
-		{ "RDB$TRIGGER_20", 1, "integ_index_mod", ODS_8_0 },
-		{ "RDB$TRIGGER_20", 2, "integ_index_deactivate", ODS_8_0 },
-		{ "RDB$TRIGGER_20", 3, "integ_deactivate_primary", ODS_8_0 },
 		{ "RDB$TRIGGER_19", 1, "integ_index_del", ODS_8_0 },
 		{ "RDB$TRIGGER_18", 1, "integ_index_seg_mod", ODS_8_0 },
 		{ "RDB$TRIGGER_17", 1, "integ_index_seg_del", ODS_8_0 },
@@ -539,7 +533,7 @@ namespace
 			const char* users[] = {userName, "PUBLIC"};
 			int grantOptions[] = {WITH_GRANT_OPTION, 0};
 
-			for (unsigned i = 0; i < FB_NELEM(users); i++)
+			for (int i = 0; i < FB_NELEM(users); i++)
 			{
 				STORE(REQUEST_HANDLE handle TRANSACTION_HANDLE transaction)
 					PRIV IN RDB$USER_PRIVILEGES
@@ -1378,6 +1372,32 @@ void INI_upgrade(thread_db* tdbb)
 	context = "triggers";
 	handle.reset();
 
+	// To be able to erase system triggers we must deactivate trigger4 first
+	jrd_rel* relTriggers = MET_lookup_relation_id(tdbb, rel_triggers, false);
+	relTriggers->rel_pre_erase->clear();
+
+	FOR(REQUEST_HANDLE handle TRANSACTION_HANDLE transaction)
+		TRG IN RDB$TRIGGERS
+		WITH TRG.RDB$SYSTEM_FLAG EQ 1
+	{
+		fb_utils::exact_name(TRG.RDB$TRIGGER_NAME);
+		bool found = false;
+		for (const jrd_trg* trigger = triggers; trigger->trg_name; ++trigger)
+		{
+			if (strcmp(TRG.RDB$TRIGGER_NAME, trigger->trg_name) == 0)
+			{
+				found = true;
+				break;
+			}
+		}
+		if (!found)
+		{
+			ERASE TRG;
+		}
+	}
+	END_FOR
+	handle.reset();
+
 	for (const jrd_trg* trigger = triggers; trigger->trg_relation; ++trigger)
 	{
 		if (trigger->trg_ods_version > odsVersion)
@@ -1387,14 +1407,34 @@ void INI_upgrade(thread_db* tdbb)
 	context = "trigger messages";
 	handle.reset();
 
+	FOR(REQUEST_HANDLE handle TRANSACTION_HANDLE transaction)
+		MSG IN RDB$TRIGGER_MESSAGES
+	{
+		fb_utils::exact_name(MSG.RDB$TRIGGER_NAME);
+		bool found = false;
+		for (const jrd_trg* trigger = triggers; trigger->trg_name; ++trigger)
+		{
+			if (strcmp(MSG.RDB$TRIGGER_NAME, trigger->trg_name) == 0)
+			{
+				found = true;
+				break;
+			}
+		}
+		if (!found)
+		{
+			ERASE MSG;
+		}
+	}
+	END_FOR
+	handle.reset();
+
 	for (const trigger_msg* message = trigger_messages; message->trigmsg_name; ++message)
 	{
 		if (message->trg_ods_version > odsVersion)
 			store_message(tdbb, message, handle);
 	}
 
 	// Create new system generators
-
 	context = "generators";
 	handle.reset();