diff --git a/manifest b/manifest
index 88b791ee16..dc0dc6bdf5 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\sa\scode\sgenerator\sbug\scaused\sby\sthe\snew\sCSE\soptimization.\s\sAdd\stest\scases\nto\sprevent\sa\srecurrence.\s(CVS\s5011)
-D 2008-04-15T12:14:22
+C Do\snot\sattempt\sto\somit\sunused\scolumns\sof\sa\sview\sin\san\sinstead-of\strigger\nsince\ssometimes\sthose\scolumns\scan\sbe\sused\sin\sways\sthat\swe\sdo\snot\sexpect.\nTicket\s#3055.\s(CVS\s5012)
+D 2008-04-15T14:36:42
 F Makefile.arm-wince-mingw32ce-gcc ac5f7b2cef0cd850d6f755ba6ee4ab961b1fadf7
 F Makefile.in 25b3282a4ac39388632c2fb0e044ff494d490952
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -93,7 +93,7 @@ F src/build.c e6f17bbb031c78e55389e3b90cd5cb150efef2b1
 F src/callback.c 77b302b0d41468dcda78c70e706e5b84577f0fa0
 F src/complete.c 4cf68fd75d60257524cbe74f87351b9848399131
 F src/date.c e41ce4513fb0e359dc678d6bddb4ace135fe365d
-F src/delete.c 555cedf9e59db9ead1c2f8db0c4344201ea7caaa
+F src/delete.c e4bd53c46969c9fb05cfbba4abc0c93a923f8072
 F src/experimental.c 1b2d1a6cd62ecc39610e97670332ca073c50792b
 F src/expr.c 7aecda0fb4f078718281a9b56993677c1f45a399
 F src/fault.c 83057e86815d473e526f7df0b0108dfdd022ff23
@@ -140,7 +140,7 @@ F src/server.c 087b92a39d883e3fa113cae259d64e4c7438bc96
 F src/shell.c 22297fffa6f00a6c6d44020fa13b1184a1bb372d
 F src/sqlite.h.in 824f823b341e9c979f82edebf710c87b74d1b7f5
 F src/sqlite3ext.h faacd0e6a81aabee0861c6d7883c9172e74ef5b3
-F src/sqliteInt.h ef381f6a169d824e8ba54a389187836c4cd48420
+F src/sqliteInt.h 625375d9327f0d79bf6f0f7864cc4a0543aec440
 F src/sqliteLimit.h f435e728c6b620ef7312814d660a81f9356eb5c8
 F src/table.c 2c48c575dd59b3a6c5c306bc55f51a9402cf429a
 F src/tclsqlite.c c4892f48927cb3db19faeb448ea8abddfd4846a8
@@ -171,7 +171,7 @@ F src/test_tclvar.c b2d1115e4d489179d3f029e765211b2ad527ba59
 F src/test_thread.c e297dd41db0b249646e69f97d36ec13e56e8b730
 F src/tokenize.c a96abe15a8db6fea2e964cdce2acba9ed17bc26f
 F src/trigger.c 9bd3b6fa0beff4a02d262c96466f752ec15a7fc3
-F src/update.c d6f214aad7eab5aaec5f966058b0828b3f7d6706
+F src/update.c 57282dae1ffffaf4aedc3201ed77f8ef09be4f45
 F src/utf.c 8c94fa10efc78c2568d08d436acc59df4df7191b
 F src/util.c 8b17ea7ad27914c6e2c4a377ca7db743fb7e29a8
 F src/vacuum.c 3524411bfb58aac0d87eadd3e5b7cd532772af30
@@ -200,7 +200,7 @@ F test/attach.test 4ab582932e3c815689f61afcdb9bce245f0bac53
 F test/attach2.test a295d2d7061adcee5884ef4a93c7c96a82765437
 F test/attach3.test 7b92dc8e40c1ebca9732ca6f2d3fefbd46f196df
 F test/attachmalloc.test 56c5e55563dba6d64641ef2f70ce06900df16912
-F test/auth.test d5896499f901eeda88c9f441b13aaccf22d5ceee
+F test/auth.test 100cde29a9913530994289038ec80ef5f63d38d3
 F test/auth2.test 65ac294b8d52cbdd463f61e77ad0165268373126
 F test/autoinc.test 0555aa5c789520f16d86a39c6c49b87998e01bea
 F test/autovacuum.test 4339e66003b9cf813dd667a83aed2dee27c4c36d
@@ -513,6 +513,7 @@ F test/trigger7.test 194984b3f6f851eb905cd0a7bffac09f36cf1244
 F test/trigger8.test 3a09275aa2214fdff56f731b1e775d8dfee4408a
 F test/trigger9.test b42703c378916d52a5e240ba98b25b155d3927a3
 F test/triggerA.test 8dbf5bffa3190bd513785a24a573a166a885fc1b
+F test/triggerB.test abee76e59736a2d10b726d4d361e1ac2e0ce3309
 F test/types.test 98e7a631bddf0806204358b452b02d0e319318a6
 F test/types2.test 3555aacf8ed8dc883356e59efc314707e6247a84
 F test/types3.test b730a7db03ef69f0fdb85b2addc20d1a0a04039b
@@ -629,7 +630,7 @@ F www/tclsqlite.tcl 8be95ee6dba05eabcd27a9d91331c803f2ce2130
 F www/vdbe.tcl 87a31ace769f20d3627a64fa1fade7fed47b90d0
 F www/version3.tcl 890248cf7b70e60c383b0e84d77d5132b3ead42b
 F www/whentouse.tcl fc46eae081251c3c181bd79c5faef8195d7991a5
-P c5435f71efa0b34c759bac4a15fdf43abf39ddfc
-R 6394eb4f4998e17e7d31653fe6234a16
+P d04246a46399e839e70b1bd57e209f80143f0d5b
+R 9aa82907da3af5df652408937e80bf8c
 U drh
-Z de8ad5aae1cda6ab722570506572bc31
+Z f9388fd458988059dfc693a19920893a
diff --git a/manifest.uuid b/manifest.uuid
index 2cd40deecc..5639ef5d5a 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-d04246a46399e839e70b1bd57e209f80143f0d5b
\ No newline at end of file
+f5fc42e96d36b78797d7fa10b01d22b8501112b1
\ No newline at end of file
diff --git a/src/delete.c b/src/delete.c
index 64ce044c1e..3c288d39a4 100644
--- a/src/delete.c
+++ b/src/delete.c
@@ -12,7 +12,7 @@
 ** This file contains C code routines that are called by the parser
 ** in order to generate code for DELETE FROM statements.
 **
-** $Id: delete.c,v 1.167 2008/04/11 19:18:25 drh Exp $
+** $Id: delete.c,v 1.168 2008/04/15 14:36:42 drh Exp $
 */
 #include "sqliteInt.h"
 
@@ -91,7 +91,6 @@ void sqlite3MaterializeView(
   Parse *pParse,       /* Parsing context */
   Select *pView,       /* View definition */
   Expr *pWhere,        /* Optional WHERE clause to be added */
-  u32 col_mask,        /* Render only the columns in this mask. */
   int iCur             /* Cursor number for ephemerial table */
 ){
   SelectDest dest;
@@ -106,7 +105,6 @@ void sqlite3MaterializeView(
     pFrom = sqlite3SrcListAppendFromTerm(pParse, 0, 0, 0, 0, pDup, 0, 0);
     pDup = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
   }
-  sqlite3SelectMask(pParse, pDup, col_mask);
   sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
   sqlite3Select(pParse, pDup, &dest, 0, 0, 0, 0);
   sqlite3SelectDelete(pDup);
@@ -248,7 +246,7 @@ void sqlite3DeleteFrom(
   ** a ephemeral table.
   */
   if( isView ){
-    sqlite3MaterializeView(pParse, pTab->pSelect, pWhere, old_col_mask, iCur);
+    sqlite3MaterializeView(pParse, pTab->pSelect, pWhere, iCur);
   }
 
   /* Resolve the column names in the WHERE clause.
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 6ff5b1f4bd..78abb7de8d 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -11,7 +11,7 @@
 *************************************************************************
 ** Internal interface definitions for SQLite.
 **
-** @(#) $Id: sqliteInt.h,v 1.692 2008/04/15 12:14:22 drh Exp $
+** @(#) $Id: sqliteInt.h,v 1.693 2008/04/15 14:36:42 drh Exp $
 */
 #ifndef _SQLITEINT_H_
 #define _SQLITEINT_H_
@@ -1935,7 +1935,7 @@ void sqlite3RegisterDateTimeFunctions(sqlite3*);
 int sqlite3SafetyCheckOk(sqlite3*);
 int sqlite3SafetyCheckSickOrOk(sqlite3*);
 void sqlite3ChangeCookie(Parse*, int);
-void sqlite3MaterializeView(Parse*, Select*, Expr*, u32, int);
+void sqlite3MaterializeView(Parse*, Select*, Expr*, int);
 
 #ifndef SQLITE_OMIT_TRIGGER
   void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
@@ -1955,14 +1955,12 @@ void sqlite3MaterializeView(Parse*, Select*, Expr*, u32, int);
   TriggerStep *sqlite3TriggerDeleteStep(sqlite3*,Token*, Expr*);
   void sqlite3DeleteTrigger(Trigger*);
   void sqlite3UnlinkAndDeleteTrigger(sqlite3*,int,const char*);
-  void sqlite3SelectMask(Parse *, Select *, u32);
 #else
 # define sqlite3TriggersExist(A,B,C,D,E,F) 0
 # define sqlite3DeleteTrigger(A)
 # define sqlite3DropTriggerPtr(A,B)
 # define sqlite3UnlinkAndDeleteTrigger(A,B,C)
 # define sqlite3CodeRowTrigger(A,B,C,D,E,F,G,H,I,J,K) 0
-# define sqlite3SelectMask(A, B, C)
 #endif
 
 int sqlite3JoinType(Parse*, Token*, Token*, Token*);
diff --git a/src/update.c b/src/update.c
index 0d8e61ab6c..2a170366a3 100644
--- a/src/update.c
+++ b/src/update.c
@@ -12,7 +12,7 @@
 ** This file contains C code routines that are called by the parser
 ** to handle UPDATE statements.
 **
-** $Id: update.c,v 1.176 2008/04/10 13:33:18 drh Exp $
+** $Id: update.c,v 1.177 2008/04/15 14:36:42 drh Exp $
 */
 #include "sqliteInt.h"
 
@@ -329,8 +329,7 @@ void sqlite3Update(
   ** a ephemeral table.
   */
   if( isView ){
-    sqlite3MaterializeView(pParse, pTab->pSelect, pWhere,
-                           old_col_mask|new_col_mask, iCur);
+    sqlite3MaterializeView(pParse, pTab->pSelect, pWhere, iCur);
   }
 
   /* Resolve the column names in all the expressions in the
diff --git a/test/auth.test b/test/auth.test
index 320826980d..82032a0bac 100644
--- a/test/auth.test
+++ b/test/auth.test
@@ -12,7 +12,7 @@
 # focus of this script is testing the sqlite3_set_authorizer() API
 # and related functionality.
 #
-# $Id: auth.test,v 1.41 2008/02/12 16:52:14 drh Exp $
+# $Id: auth.test,v 1.42 2008/04/15 14:36:42 drh Exp $
 #
 
 set testdir [file dirname $argv0]
@@ -2248,10 +2248,10 @@ do_test auth-4.3 {
   SQLITE_INSERT v1chng {} main r2 \
   SQLITE_READ   v1     x  main r2 \
   SQLITE_READ   v1     x  main r2 \
+  SQLITE_SELECT {}     {} {}   v1 \
   SQLITE_READ   t2     a  main v1 \
   SQLITE_READ   t2     b  main v1 \
   SQLITE_SELECT {}     {} {}   v1 \
-  SQLITE_SELECT {}     {} {}   v1 \
   SQLITE_READ   v1     x  main v1 \
 ]
 do_test auth-4.4 {
@@ -2272,10 +2272,10 @@ do_test auth-4.5 {
   SQLITE_DELETE v1     {} main {} \
   SQLITE_INSERT v1chng {} main r3 \
   SQLITE_READ   v1     x  main r3 \
+  SQLITE_SELECT {}     {} {}   v1 \
   SQLITE_READ   t2     a  main v1 \
   SQLITE_READ   t2     b  main v1 \
   SQLITE_SELECT {}     {} {}   v1 \
-  SQLITE_SELECT {}     {} {}   v1 \
   SQLITE_READ   v1     x  main v1 \
 ]
 
diff --git a/test/triggerB.test b/test/triggerB.test
new file mode 100644
index 0000000000..5028152d5a
--- /dev/null
+++ b/test/triggerB.test
@@ -0,0 +1,45 @@
+# 2008 April 15
+#
+# The author disclaims copyright to this source code.  In place of
+# a legal notice, here is a blessing:
+#
+#    May you do good and not evil.
+#    May you find forgiveness for yourself and forgive others.
+#    May you share freely, never taking more than you give.
+#
+#***********************************************************************
+# This file implements regression tests for SQLite library. Specifically,
+# it tests updating tables with constraints within a trigger.  Ticket #3055.
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+ifcapable {!trigger} {
+  finish_test
+  return
+}
+
+# Create test tables with constraints.
+#
+do_test triggerB-1.1 {
+  execsql {
+    CREATE TABLE x(x INTEGER PRIMARY KEY, y INT NOT NULL);
+    INSERT INTO x(y) VALUES(1);
+    INSERT INTO x(y) VALUES(1);
+    CREATE TEMP VIEW vx AS SELECT x, y, 0 AS yy FROM x;
+    CREATE TEMP TRIGGER tx INSTEAD OF UPDATE OF y ON vx
+    BEGIN
+      UPDATE x SET y = new.y WHERE x = new.x;
+    END;
+    SELECT * FROM vx;
+  }
+} {1 1 0 2 1 0}
+do_test triggerB-1.2 {
+breakpoint
+  execsql {
+    UPDATE vx SET y = yy;
+    SELECT * FROM vx;
+  }
+} {1 0 0 2 0 0}
+
+finish_test