Disable index lookups in join optimization if index is case sensitive, but argument is not.

Modified test script to avoid coincidental success ('HElLo' < 'Hello')

h2/src/main/org/h2/expression/Comparison.java

@@ -465,12 +465,16 @@ public class Comparison extends Condition {
         }
         if (addIndex) {
             if (l != null) {
-                filter.addIndexCondition(
-                        IndexCondition.get(compareType, l, right));
+                if (l.getType() == right.getType() || right.getType() != Value.STRING_IGNORECASE) {
+                    filter.addIndexCondition(
+                            IndexCondition.get(compareType, l, right));
+                }
             } else if (r != null) {
-                int compareRev = getReversedCompareType(compareType);
-                filter.addIndexCondition(
-                        IndexCondition.get(compareRev, r, left));
+                if (r.getType() == left.getType() || left.getType() != Value.STRING_IGNORECASE) {
+                    int compareRev = getReversedCompareType(compareType);
+                    filter.addIndexCondition(
+                            IndexCondition.get(compareRev, r, left));
+                }
             }
         }
     }

h2/src/main/org/h2/expression/ExpressionColumn.java

@@ -199,7 +199,7 @@ public class ExpressionColumn extends Expression {
 
     @Override
     public int getType() {
-        return column.getType();
+        return column == null ? Value.UNKNOWN : column.getType();
     }
 
     @Override

h2/src/test/org/h2/test/scripts/testScript.sql

@@ -2866,7 +2866,7 @@ CREATE TABLE TEST2(ID INT PRIMARY KEY, NAME VARCHAR(255));
 create unique index idx_test2_name on test2(name);
 > ok
 
-INSERT INTO TEST2 VALUES(1, 'HElLo');
+INSERT INTO TEST2 VALUES(1, 'hElLo');
 > update count: 1
 
 INSERT INTO TEST2 VALUES(2, 'World');
@@ -2886,7 +2886,7 @@ select * from test where name='HELLO';
 select * from test2 where name='HELLO';
 > ID NAME
 > -- -----
-> 1  HElLo
+> 1  hElLo
 > rows: 1
 
 select * from test where name like 'HELLO';
@@ -2897,26 +2897,26 @@ select * from test where name like 'HELLO';
 select * from test2 where name like 'HELLO';
 > ID NAME
 > -- -----
-> 1  HElLo
+> 1  hElLo
 > rows: 1
 
 explain plan for select * from test2, test where test2.name = test.name;
->> SELECT TEST2.ID, TEST2.NAME, TEST.ID, TEST.NAME FROM PUBLIC.TEST2 /* PUBLIC.TEST2.tableScan */ INNER JOIN PUBLIC.TEST /* PUBLIC.IDX_TEST_NAME: NAME = TEST2.NAME */ ON 1=1 WHERE TEST2.NAME = TEST.NAME
+>> SELECT TEST2.ID, TEST2.NAME, TEST.ID, TEST.NAME FROM PUBLIC.TEST2 /* PUBLIC.TEST2.tableScan */ INNER JOIN PUBLIC.TEST /* PUBLIC.TEST.tableScan */ ON 1=1 WHERE TEST2.NAME = TEST.NAME
 
 select * from test2, test where test2.name = test.name;
 > ID NAME  ID NAME
 > -- ----- -- -----
-> 1  HElLo 1  Hello
+> 1  hElLo 1  Hello
 > 2  World 2  World
 > rows: 2
 
 explain plan for select * from test, test2 where test2.name = test.name;
->> SELECT TEST.ID, TEST.NAME, TEST2.ID, TEST2.NAME FROM PUBLIC.TEST2 /* PUBLIC.TEST2.tableScan */ INNER JOIN PUBLIC.TEST /* PUBLIC.IDX_TEST_NAME: NAME = TEST2.NAME */ ON 1=1 WHERE TEST2.NAME = TEST.NAME
+>> SELECT TEST.ID, TEST.NAME, TEST2.ID, TEST2.NAME FROM PUBLIC.TEST2 /* PUBLIC.TEST2.tableScan */ INNER JOIN PUBLIC.TEST /* PUBLIC.TEST.tableScan */ ON 1=1 WHERE TEST2.NAME = TEST.NAME
 
 select * from test, test2 where test2.name = test.name;
 > ID NAME  ID NAME
 > -- ----- -- -----
-> 1  Hello 1  HElLo
+> 1  Hello 1  hElLo
 > 2  World 2  World
 > rows: 2
 
@@ -2924,12 +2924,12 @@ create index idx_test2_name on test2(name);
 > ok
 
 explain plan for select * from test2, test where test2.name = test.name;
->> SELECT TEST2.ID, TEST2.NAME, TEST.ID, TEST.NAME FROM PUBLIC.TEST2 /* PUBLIC.TEST2.tableScan */ INNER JOIN PUBLIC.TEST /* PUBLIC.IDX_TEST_NAME: NAME = TEST2.NAME */ ON 1=1 WHERE TEST2.NAME = TEST.NAME
+>> SELECT TEST2.ID, TEST2.NAME, TEST.ID, TEST.NAME FROM PUBLIC.TEST /* PUBLIC.TEST.tableScan */ INNER JOIN PUBLIC.TEST2 /* PUBLIC.IDX_TEST2_NAME: NAME = TEST.NAME */ ON 1=1 WHERE TEST2.NAME = TEST.NAME
 
 select * from test2, test where test2.name = test.name;
 > ID NAME  ID NAME
 > -- ----- -- -----
-> 1  HElLo 1  Hello
+> 1  hElLo 1  Hello
 > 2  World 2  World
 > rows: 2
 
@@ -2939,7 +2939,7 @@ explain plan for select * from test, test2 where test2.name = test.name;
 select * from test, test2 where test2.name = test.name;
 > ID NAME  ID NAME
 > -- ----- -- -----
-> 1  Hello 1  HElLo
+> 1  Hello 1  hElLo
 > 2  World 2  World
 > rows: 2