diff --git a/manifest b/manifest
index ecec19fcc6..85667fe53f 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Require\sthe\sINSTEAD\sOF\ssyntax\sto\screate\striggers\son\sdatabase\sviews.\s(CVS\s591)
-D 2002-05-26T23:24:41
+C Bug\sfixes\sand\sadditional\stest\scases\sfor\sthe\sdistinct-NULL\spatch.\s(CVS\s592)
+D 2002-05-27T01:04:51
 F Makefile.in 6291a33b87d2a395aafd7646ee1ed562c6f2c28c
 F Makefile.template 4e11752e0b5c7a043ca50af4296ec562857ba495
 F README a4c0ba11354ef6ba0776b400d057c59da47a4cc0
@@ -52,7 +52,7 @@ F src/tokenize.c facec7dc0b4a13e17ad67702f548dac2f7c6a732
 F src/trigger.c b7a93ffa7b91dafff433e6c87d603bfb1d50e3ee
 F src/update.c f68375173bf5338cae3e97012708e10f206aedd9
 F src/util.c a9f6e6f03e8b7137204ac15b35a58f321e38037e
-F src/vdbe.c caa269517b2392986c8f55401f272e76b9de82d9
+F src/vdbe.c ccbee9fb9b98a2fc75400865d69531da36cbf0f1
 F src/vdbe.h b8706429131c14b307a07aab7e47f95a9da53610
 F src/where.c b054f2f23127bd57eb5f973bcd38764b875d73fe
 F test/all.test e4d3821eeba751829b419cd47814bd20af4286d1
@@ -63,8 +63,8 @@ F test/btree3.test 9caa9e22491dd8cd8aa36d7ac3b48b089817c895
 F test/conflict.test 5149646703d3930c9111068b5cda7e2e938476e3
 F test/copy.test b3cefcb520c64d7e7dfedbab06b4d4c31fa5b99a
 F test/delete.test c904a62129fe102b314a96111a8417f10249e4d8
-F test/expr.test bfb773721e69566d2a7565c7f03b466e1f33a53f
-F test/func.test d34e461f0acb0cf2978a4b3a3e098460f2ea8fbc
+F test/expr.test 518ee35ec8d2c8883544d75a031219c75391fb21
+F test/func.test 1505ac9ebc11ca5c0300192d1519a542d5cbcfe1
 F test/in.test c09312672e3f0709fa02c8e2e9cd8fb4bd6269aa
 F test/index.test c8a471243bbf878974b99baf5badd59407237cf3
 F test/insert.test 58d44c19b3557f67f4aeb5110ed9ef02038c3684
@@ -76,7 +76,7 @@ F test/limit.test 6f98bcefc92209103bb3764c81975a6ec21d6702
 F test/lock.test 3fcfd46a73119f6a18094673328a32c7b3047a8f
 F test/main.test c66b564554b770ee7fdbf6a66c0cd90329bc2c85
 F test/malloc.test 7ba32a9ebd3aeed52ae4aaa6d42ca37e444536fd
-F test/minmax.test fb6ab400271ae1f5bc88617c2882f2f081ea8e6d
+F test/minmax.test c50bcc760433acd7ca8e22bc4c525b9ae82762e2
 F test/misc1.test df281e9b26cd1db5808939c7cf2703072d555be0
 F test/misuse.test a3aa2b18a97e4c409a1fcaff5151a4dd804a0162
 F test/notnull.test b1f3e42fc475b0b5827b27b2e9b562081995ff30
@@ -86,10 +86,10 @@ F test/printf.test 3cb415073754cb8ff076f26173143c3cd293a9da
 F test/quick.test 6f023c7a73fc413e6d65b7a1879c79764038dc05
 F test/quote.test 08f23385c685d3dc7914ec760d492cacea7f6e3d
 F test/rowid.test 4c55943300cddf73dd0f88d40a268cab14c83274
-F test/select1.test 6ba20b52d563b7fb917d8a61a7560d02f90a1a52
+F test/select1.test 4e1ac9cc3cbf5b3ceae388fb3d4ca1b9f9a1cc15
 F test/select2.test aceea74fd895b9d007512f72499db589735bd8e4
 F test/select3.test 9469c332250a75a0ef1771fb5da62dc04ec77f18
-F test/select4.test 0bc0065102573c6b71003292fd4a5def63923c61
+F test/select4.test 2ea8c7b7feceb853da167a39e4cce996a5c3ad88
 F test/select5.test c2a6c4a003316ee42cbbd689eebef8fdce0db2ac
 F test/select6.test efb8d0c07a440441db87db2c4ade6904e1407e85
 F test/sort.test 3b996ce7ca385f9cd559944ac0f4027a23aa546b
@@ -135,7 +135,7 @@ F www/speed.tcl da8afcc1d3ccc5696cfb388a68982bc3d9f7f00f
 F www/sqlite.tcl 8b5884354cb615049aed83039f8dfe1552a44279
 F www/tclsqlite.tcl 1db15abeb446aad0caf0b95b8b9579720e4ea331
 F www/vdbe.tcl 2013852c27a02a091d39a766bc87cff329f21218
-P 46ce1a9ab6e527958ebc757fa2175c488299cd84
-R 35b518a6cb0a7aed91c92408e7bd6686
-U danielk1977
-Z 9e3f1ec0355281ef07dac5144d661dfb
+P d9e48cd5180e2aae7672b9d54e18c37d0fe5258a
+R fc93e940356a8b3ec291e98d6e7a4c6b
+U drh
+Z b54c0b1652f6c89ad5dde6fb5c2177ec
diff --git a/manifest.uuid b/manifest.uuid
index 6cf893c246..c1e4a62103 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-d9e48cd5180e2aae7672b9d54e18c37d0fe5258a
\ No newline at end of file
+0e268d0c0faa02c3f95e1567cf631b7a04bfbdf0
\ No newline at end of file
diff --git a/src/vdbe.c b/src/vdbe.c
index fa558eb7cc..19d7ed78d7 100644
--- a/src/vdbe.c
+++ b/src/vdbe.c
@@ -30,7 +30,7 @@
 ** But other routines are also provided to help in building up
 ** a program instruction by instruction.
 **
-** $Id: vdbe.c,v 1.149 2002/05/26 20:54:34 drh Exp $
+** $Id: vdbe.c,v 1.150 2002/05/27 01:04:51 drh Exp $
 */
 #include "sqliteInt.h"
 #include <ctype.h>
@@ -2132,38 +2132,47 @@ case OP_Ge: {
 ** Pop two values off the stack.  Take the logical AND of the
 ** two values and push the resulting boolean value back onto the
 ** stack. 
-** If either operand is NULL, the result is NULL.
 */
 /* Opcode: Or * * *
 **
 ** Pop two values off the stack.  Take the logical OR of the
 ** two values and push the resulting boolean value back onto the
 ** stack. 
-** If either operand is NULL, the result is NULL.
 */
 case OP_And:
 case OP_Or: {
   int tos = p->tos;
   int nos = tos - 1;
-  int c;
+  int v1, v2;    /* 0==TRUE, 1==FALSE, 2==UNKNOWN or NULL */
+
   VERIFY( if( nos<0 ) goto not_enough_stack; )
-  if( (aStack[tos].flags | aStack[nos].flags) & STK_Null ){
-    POPSTACK;
-    Release(p, nos);     
-    aStack[nos].flags = STK_Null;
-    break;
-  }
-  Integerify(p, tos);
-  Integerify(p, nos);
-  if( pOp->opcode==OP_And ){
-    c = aStack[tos].i && aStack[nos].i;
+  if( aStack[tos].flags & STK_Null ){
+    v1 = 2;
   }else{
-    c = aStack[tos].i || aStack[nos].i;
+    Integerify(p, tos);
+    v1 = aStack[tos].i==0;
+  }
+  if( aStack[nos].flags & STK_Null ){
+    v2 = 2;
+  }else{
+    Integerify(p, nos);
+    v2 = aStack[nos].i==0;
+  }
+  if( pOp->opcode==OP_And ){
+    static const unsigned char and_logic[] = { 0, 1, 2, 1, 1, 1, 2, 1, 2 };
+    v1 = and_logic[v1*3+v2];
+  }else{
+    static const unsigned char or_logic[] = { 0, 0, 0, 0, 1, 2, 0, 2, 2 };
+    v1 = or_logic[v1*3+v2];
   }
   POPSTACK;
-  Release(p, nos);     
-  aStack[nos].i = c;
-  aStack[nos].flags = STK_Int;
+  Release(p, nos);
+  if( v1==2 ){
+    aStack[nos].flags = STK_Null;
+  }else{
+    aStack[nos].i = v1==0;
+    aStack[nos].flags = STK_Int;
+  }
   break;
 }
 
diff --git a/test/expr.test b/test/expr.test
index 0d93df6627..2d2a96a0b2 100644
--- a/test/expr.test
+++ b/test/expr.test
@@ -11,7 +11,7 @@
 # This file implements regression tests for SQLite library.  The
 # focus of this file is testing expressions.
 #
-# $Id: expr.test,v 1.20 2002/05/26 20:54:34 drh Exp $
+# $Id: expr.test,v 1.21 2002/05/27 01:04:51 drh Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -82,6 +82,47 @@ test_expr expr-1.53 {i1=099999999999, i2=99999999999} {i1<i2} 0
 test_expr expr-1.54 {i1=099999999999, i2=99999999999} {i1=i2} 1
 test_expr expr-1.55 {i1=099999999999, i2=99999999999} {i1>i2} 0
 test_expr expr-1.56 {i1=25, i2=11} {i1%i2} 3
+test_expr expr-1.58 {i1=NULL, i2=1} {coalesce(i1+i2,99)} 99
+test_expr expr-1.59 {i1=1, i2=NULL} {coalesce(i1+i2,99)} 99
+test_expr expr-1.60 {i1=NULL, i2=NULL} {coalesce(i1+i2,99)} 99
+test_expr expr-1.61 {i1=NULL, i2=1} {coalesce(i1-i2,99)} 99
+test_expr expr-1.62 {i1=1, i2=NULL} {coalesce(i1-i2,99)} 99
+test_expr expr-1.63 {i1=NULL, i2=NULL} {coalesce(i1-i2,99)} 99
+test_expr expr-1.64 {i1=NULL, i2=1} {coalesce(i1*i2,99)} 99
+test_expr expr-1.65 {i1=1, i2=NULL} {coalesce(i1*i2,99)} 99
+test_expr expr-1.66 {i1=NULL, i2=NULL} {coalesce(i1*i2,99)} 99
+test_expr expr-1.67 {i1=NULL, i2=1} {coalesce(i1/i2,99)} 99
+test_expr expr-1.68 {i1=1, i2=NULL} {coalesce(i1/i2,99)} 99
+test_expr expr-1.69 {i1=NULL, i2=NULL} {coalesce(i1/i2,99)} 99
+test_expr expr-1.70 {i1=NULL, i2=1} {coalesce(i1<i2,99)} 99
+test_expr expr-1.71 {i1=1, i2=NULL} {coalesce(i1>i2,99)} 99
+test_expr expr-1.72 {i1=NULL, i2=NULL} {coalesce(i1<=i2,99)} 99
+test_expr expr-1.73 {i1=NULL, i2=1} {coalesce(i1>=i2,99)} 99
+test_expr expr-1.74 {i1=1, i2=NULL} {coalesce(i1!=i2,99)} 99
+test_expr expr-1.75 {i1=NULL, i2=NULL} {coalesce(i1==i2,99)} 99
+test_expr expr-1.76 {i1=NULL, i2=NULL} {coalesce(not i1,99)} 99
+test_expr expr-1.77 {i1=NULL, i2=NULL} {coalesce(-i1,99)} 99
+test_expr expr-1.78 {i1=NULL, i2=NULL} {coalesce(i1 IS NULL AND i2=5,99)} 99
+test_expr expr-1.79 {i1=NULL, i2=NULL} {coalesce(i1 IS NULL OR i2=5,99)} 1
+test_expr expr-1.80 {i1=NULL, i2=NULL} {coalesce(i1=5 AND i2 IS NULL,99)} 99
+test_expr expr-1.81 {i1=NULL, i2=NULL} {coalesce(i1=5 OR i2 IS NULL,99)} 1
+test_expr expr-1.82 {i1=NULL, i2=3} {coalesce(min(i1,i2,1),99)} 99
+test_expr expr-1.83 {i1=NULL, i2=3} {coalesce(max(i1,i2,1),99)} 99
+test_expr expr-1.84 {i1=3, i2=NULL} {coalesce(min(i1,i2,1),99)} 99
+test_expr expr-1.85 {i1=3, i2=NULL} {coalesce(max(i1,i2,1),99)} 99
+test_expr expr-1.86 {i1=3, i2=8} {5 between i1 and i2} 1
+test_expr expr-1.87 {i1=3, i2=8} {5 not between i1 and i2} 0
+test_expr expr-1.88 {i1=3, i2=8} {55 between i1 and i2} 0
+test_expr expr-1.89 {i1=3, i2=8} {55 not between i1 and i2} 1
+test_expr expr-1.90 {i1=3, i2=NULL} {5 between i1 and i2} {{}}
+test_expr expr-1.91 {i1=3, i2=NULL} {5 not between i1 and i2} {{}}
+test_expr expr-1.92 {i1=3, i2=NULL} {2 between i1 and i2} 0
+test_expr expr-1.93 {i1=3, i2=NULL} {2 not between i1 and i2} 1
+test_expr expr-1.94 {i1=NULL, i2=8} {2 between i1 and i2} {{}}
+test_expr expr-1.95 {i1=NULL, i2=8} {2 not between i1 and i2} {{}}
+test_expr expr-1.94 {i1=NULL, i2=8} {55 between i1 and i2} 0
+test_expr expr-1.95 {i1=NULL, i2=8} {55 not between i1 and i2} 1
+
 
 test_expr expr-2.1 {r1=1.23, r2=2.34} {r1+r2} 3.57
 test_expr expr-2.2 {r1=1.23, r2=2.34} {r1-r2} -1.11
@@ -107,6 +148,7 @@ test_expr expr-2.21 {r1=2.34, r2=2.34} {r2==r1} 1
 test_expr expr-2.22 {r1=1.23, r2=2.34} {min(r1,r2,r1+r2,r1-r2)} {-1.11}
 test_expr expr-2.23 {r1=1.23, r2=2.34} {max(r1,r2,r1+r2,r1-r2)} {3.57}
 test_expr expr-2.24 {r1=25.0, r2=11.0} {r1%r2} 3
+test_expr expr-2.25 {r1=1.23, r2=NULL} {coalesce(r1+r2,99.0)} 99.0
 
 test_expr expr-3.1 {t1='abc', t2='xyz'} {t1<t2} 1
 test_expr expr-3.2 {t1='xyz', t2='abc'} {t1<t2} 0
@@ -205,6 +247,11 @@ if {[sqlite -encoding]=="iso8859"} {
     test_expr expr-5.53 "t1='ax\241', t2='A_%'"  {t1 LIKE t2} 1
   }
 }
+test_expr expr-5.54 {t1='abc', t2=NULL} {t1 LIKE t2} {{}}
+test_expr expr-5.55 {t1='abc', t2=NULL} {t1 NOT LIKE t2} {{}}
+test_expr expr-5.56 {t1='abc', t2=NULL} {t2 LIKE t1} {{}}
+test_expr expr-5.57 {t1='abc', t2=NULL} {t2 NOT LIKE t1} {{}}
+
 
 test_expr expr-6.1 {t1='abc', t2='xyz'} {t1 GLOB t2} 0
 test_expr expr-6.2 {t1='abc', t2='ABC'} {t1 GLOB t2} 0
@@ -232,21 +279,6 @@ test_expr expr-6.23 {t1='abcdefg', t2='a*?g'} {t1 GLOB t2} 1
 test_expr expr-6.24 {t1='ac', t2='a*c'} {t1 GLOB t2} 1
 test_expr expr-6.25 {t1='ac', t2='a*?c'} {t1 GLOB t2} 0
 
-test_expr expr-case.1 {i1=1, i2=2} \
-	{CASE WHEN i1 = i2 THEN 'eq' ELSE 'ne' END} ne
-test_expr expr-case.2 {i1=2, i2=2} \
-	{CASE WHEN i1 = i2 THEN 'eq' ELSE 'ne' END} eq
-test_expr expr-case.3 {i1=2} \
-	{CASE i1 WHEN 1 THEN 'one' WHEN 2 THEN 'two' ELSE 'error' END} two
-test_expr expr-case.4 {i1=3} \
-	{CASE i1 WHEN 1 THEN 'one' WHEN 2 THEN 'two' ELSE 'error' END} error
-test_expr expr-case.5 {i1=3} \
-	{CASE i1 WHEN 1 THEN 'one' WHEN 2 THEN 'two' END} {{}}
-test_expr expr-case.6 {i1=7} \
-	{ CASE WHEN i1 < 5 THEN 'low' 
-	       WHEN i1 < 10 THEN 'medium' 
-               WHEN i1 < 15 THEN 'high' ELSE 'error' END} medium
-
 
 # These tests only work on versions of TCL that support Unicode
 #
@@ -295,6 +327,36 @@ if {[sqlite -encoding]=="iso8859"} {
     test_expr expr-6.62 "t1='a\266b', t2='a\[x-\265\]b'" {t1 GLOB t2} 0
   }
 }
+test_expr expr-6.63 {t1=NULL, t2='a*?c'} {t1 GLOB t2} {{}}
+test_expr expr-6.64 {t1='ac', t2=NULL} {t1 GLOB t2} {{}}
+test_expr expr-6.65 {t1=NULL, t2='a*?c'} {t1 NOT GLOB t2} {{}}
+test_expr expr-6.66 {t1='ac', t2=NULL} {t1 NOT GLOB t2} {{}}
+
+test_expr expr-case.1 {i1=1, i2=2} \
+	{CASE WHEN i1 = i2 THEN 'eq' ELSE 'ne' END} ne
+test_expr expr-case.2 {i1=2, i2=2} \
+	{CASE WHEN i1 = i2 THEN 'eq' ELSE 'ne' END} eq
+test_expr expr-case.3 {i1=NULL, i2=2} \
+	{CASE WHEN i1 = i2 THEN 'eq' ELSE 'ne' END} {{}}
+test_expr expr-case.4 {i1=2, i2=NULL} \
+	{CASE WHEN i1 = i2 THEN 'eq' ELSE 'ne' END} {{}}
+test_expr expr-case.5 {i1=2} \
+	{CASE i1 WHEN 1 THEN 'one' WHEN 2 THEN 'two' ELSE 'error' END} two
+test_expr expr-case.6 {i1=1} \
+	{CASE i1 WHEN 1 THEN 'one' WHEN NULL THEN 'two' ELSE 'error' END} one
+test_expr expr-case.7 {i1=2} \
+	{CASE i1 WHEN 1 THEN 'one' WHEN NULL THEN 'two' ELSE 'error' END} {{}}
+test_expr expr-case.8 {i1=3} \
+	{CASE i1 WHEN 1 THEN 'one' WHEN NULL THEN 'two' ELSE 'error' END} {{}}
+test_expr expr-case.9 {i1=3} \
+	{CASE i1 WHEN 1 THEN 'one' WHEN 2 THEN 'two' ELSE 'error' END} error
+test_expr expr-case.10 {i1=3} \
+	{CASE i1 WHEN 1 THEN 'one' WHEN 2 THEN 'two' END} {{}}
+test_expr expr-case.11 {i1=7} \
+	{ CASE WHEN i1 < 5 THEN 'low' 
+	       WHEN i1 < 10 THEN 'medium' 
+               WHEN i1 < 15 THEN 'high' ELSE 'error' END} medium
+
 
 # The sqliteExprIfFalse and sqliteExprIfTrue routines are only
 # executed as part of a WHERE clause.  Create a table suitable
@@ -344,5 +406,36 @@ test_expr2 expr-7.25 {a GLOB '2?' OR a==8}           {8 20}
 test_expr2 expr-7.26 {a isnull OR a=8}               {{} 8}
 test_expr2 expr-7.27 {a notnull OR a=8} \
                           {1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20}
+test_expr2 expr-7.28 {a<0 OR b=0} {{}}
+test_expr2 expr-7.29 {b=0 OR a<0} {{}}
+test_expr2 expr-7.30 {a<0 AND b=0} {}
+test_expr2 expr-7.31 {b=0 AND a<0} {}
+test_expr2 expr-7.32 {a IS NULL AND (a<0 OR b=0)} {{}}
+test_expr2 expr-7.33 {a IS NULL AND (b=0 OR a<0)} {{}}
+test_expr2 expr-7.34 {a IS NULL AND (a<0 AND b=0)} {}
+test_expr2 expr-7.35 {a IS NULL AND (b=0 AND a<0)} {}
+test_expr2 expr-7.32 {(a<0 OR b=0) AND a IS NULL} {{}}
+test_expr2 expr-7.33 {(b=0 OR a<0) AND a IS NULL} {{}}
+test_expr2 expr-7.34 {(a<0 AND b=0) AND a IS NULL} {}
+test_expr2 expr-7.35 {(b=0 AND a<0) AND a IS NULL} {}
+test_expr2 expr-7.36 {a<2 OR (a<0 OR b=0)} {{} 1}
+test_expr2 expr-7.37 {a<2 OR (b=0 OR a<0)} {{} 1}
+test_expr2 expr-7.38 {a<2 OR (a<0 AND b=0)} {1}
+test_expr2 expr-7.39 {a<2 OR (b=0 AND a<0)} {1}
+test_expr2 expr-7.40 {((a<2 OR a IS NULL) AND b<3) OR b>1e10} {{} 1}
+test_expr2 expr-7.41 {a BETWEEN -1 AND 1} {1}
+test_expr2 expr-7.42 {a NOT BETWEEN 2 AND 100} {1}
+
+test_expr2 expr-7.50 {((a between 1 and 2 OR 0) AND 1) OR 0} {1 2}
+test_expr2 expr-7.51 {((a not between 3 and 100 OR 0) AND 1) OR 0} {1 2}
+test_expr2 expr-7.52 {((a in (1,2) OR 0) AND 1) OR 0} {1 2}
+test_expr2 expr-7.53 {((a not in (3,4,5,6,7,8,9,10) OR 0) AND a<11) OR 0} {1 2}
+test_expr2 expr-7.54 {((a>0 OR 0) AND a<3) OR 0} {1 2}
+test_expr2 expr-7.55 {((a in (1,2) OR 0) IS NULL AND 1) OR 0} {{}}
+test_expr2 expr-7.56 {((a not in (3,4,5,6,7,8,9,10) IS NULL OR 0) AND 1) OR 0} \
+   {{}}
+test_expr2 expr-7.57 {((a>0 IS NULL OR 0) AND 1) OR 0} {{}}
+
+
 
 finish_test
diff --git a/test/func.test b/test/func.test
index 64888211b8..79821ed166 100644
--- a/test/func.test
+++ b/test/func.test
@@ -11,7 +11,7 @@
 # This file implements regression tests for SQLite library.  The
 # focus of this file is testing built-in functions.
 #
-# $Id: func.test,v 1.10 2002/04/06 14:10:47 drh Exp $
+# $Id: func.test,v 1.11 2002/05/27 01:04:51 drh Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -55,8 +55,8 @@ do_test func-1.3 {
            ORDER BY length(t1)}
 } {2 1 4 2 7 1 8 1}
 do_test func-1.4 {
-  execsql {SELECT length(a) FROM t2}
-} {1 0 3 0 5}
+  execsql {SELECT coalesce(length(a),-1) FROM t2}
+} {1 -1 3 -1 5}
 
 # Check out the substr() function
 #
@@ -197,8 +197,8 @@ do_test func-4.11 {
   catchsql {SELECT round() FROM t1 ORDER BY a}
 } {1 {wrong number of arguments to function round()}}
 do_test func-4.12 {
-  execsql {SELECT round(a,2) FROM t2}
-} {1.00 0.00 345.00 0.00 67890.00}
+  execsql {SELECT coalesce(round(a,2),'nil') FROM t2}
+} {1.00 nil 345.00 nil 67890.00}
 do_test func-4.13 {
   execsql {SELECT round(t1,2) FROM tbl1}
 } {0.00 0.00 0.00 0.00 0.00}
diff --git a/test/minmax.test b/test/minmax.test
index 3639e793a7..1355121b1d 100644
--- a/test/minmax.test
+++ b/test/minmax.test
@@ -13,7 +13,7 @@
 # aggregate min() and max() functions and which are handled as
 # as a special case.
 #
-# $Id: minmax.test,v 1.1 2002/02/19 22:42:06 drh Exp $
+# $Id: minmax.test,v 1.2 2002/05/27 01:04:51 drh Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -122,5 +122,11 @@ do_test minmax-3.3 {
   set sqlite_search_count
 } {0}
 
+do_test minmax-4.1 {
+  execsql {
+    SELECT coalesce(min(x),-1), coalesce(max(x),-1) FROM
+      (SELECT * FROM t1 UNION SELECT NULL as 'x', NULL as 'y')
+  }
+} {-1 -1}
 
 finish_test
diff --git a/test/select1.test b/test/select1.test
index 304181bf47..8a59498a01 100644
--- a/test/select1.test
+++ b/test/select1.test
@@ -11,7 +11,7 @@
 # This file implements regression tests for SQLite library.  The
 # focus of this file is testing the SELECT statement.
 #
-# $Id: select1.test,v 1.26 2002/05/24 20:31:38 drh Exp $
+# $Id: select1.test,v 1.27 2002/05/27 01:04:51 drh Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -188,8 +188,8 @@ do_test select1-2.13 {
 } {0 34}
 do_test select1-2.13.1 {
   execsql {SELECT coalesce(max(a),'xyzzy') FROM t3}
-} {abc}
-do_test select1-2.13.1 {
+} {xyzzy}
+do_test select1-2.13.2 {
   execsql {SELECT max(coalesce(a,'xyzzy')) FROM t3}
 } {xyzzy}
 do_test select1-2.14 {
@@ -468,10 +468,12 @@ do_test select1-8.3 {
 } {11 33}
 do_test select1-8.4 {
   execsql {
-    SELECT f1/(f1-11), min(f1/(f1-11),5), max(f1/(f1-33),6)
+    SELECT coalesce(f1/(f1-11),'x'),
+           coalesce(min(f1/(f1-11),5),'y'),
+           coalesce(max(f1/(f1-33),6),'z')
     FROM test1 ORDER BY f1
   }
-} {{} {} 6 1.5 1.5 6}
+} {x y 6 1.5 1.5 z}
 do_test select1-8.5 {
   execsql {
     SELECT min(1,2,3), -max(1,2,3)
diff --git a/test/select4.test b/test/select4.test
index 2b47b35743..cfa8eca8e7 100644
--- a/test/select4.test
+++ b/test/select4.test
@@ -12,7 +12,7 @@
 # focus of this file is testing UNION, INTERSECT and EXCEPT operators
 # in SELECT statements.
 #
-# $Id: select4.test,v 1.7 2002/05/26 20:54:35 drh Exp $
+# $Id: select4.test,v 1.8 2002/05/27 01:04:51 drh Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -290,6 +290,14 @@ do_test select4-6.6 {
   }
 } {1 2}
 
+# Test distinctness of NULL in other ways.
+#
+do_test select4-6.7 {
+  execsql {
+    SELECT NULL EXCEPT SELECT NULL
+  }
+} {{}}
+
 
 # Make sure column names are correct when a compound select appears as
 # an expression in the WHERE clause.