Updated testing of cursor-hints. Remove the test_cursorhint.c file and

associated logic in the core and do tests based purely on the newly enhanced
EXPLAIN output.

FossilOrigin-Name: bf383e665a191a4f33a540d1240960a922e22813

test/cursorhint.test

@@ -16,57 +16,108 @@ source $testdir/tester.tcl
 set testprefix cursorhint
 
 do_execsql_test 1.0 {
-  CREATE TABLE t1(a,b);
-  CREATE TABLE t2(x,y);
-  INSERT INTO t1 VALUES(10, 15);
-  INSERT INTO t1 VALUES(20, 25);
-  INSERT INTO t2 VALUES('ten', 'fifteen');
-  INSERT INTO t2 VALUES('twenty', 'twentyfive');
+  CREATE TABLE t1(a,b,c,d);
+  CREATE TABLE t2(x,y,z);
+  INSERT INTO t1(a,b) VALUES(10, 15);
+  INSERT INTO t1(a,b) VALUES(20, 25);
+  INSERT INTO t2(x,y) VALUES('ten', 'fifteen');
+  INSERT INTO t2(x,y) VALUES('twenty', 'twentyfive');
+  CREATE TABLE t3(id TEXT PRIMARY KEY, a, b, c, d) WITHOUT ROWID;
+  INSERT INTO t3(id,a,b,c,d) SELECT rowid, a, b, c, d FROM t1;
   PRAGMA automatic_index = 0;
 }
 
-proc H {expr} {
-  lappend ::cursorhint $expr
+# Run EXPLAIN on $sql.  Return a list of P4 values for all $opcode
+# opcodes.
+#
+proc p4_of_opcode {db opcode sql} {
+  set res {}
+  $db eval "EXPLAIN $sql" x {
+    if {$x(opcode)==$opcode} {lappend res $x(p4)}
+  }
+  return $res
 }
 
-proc do_cursorhint_test {tn sql hints} {
-  cursorhint_hook H
-  set ::cursorhint [list]
-  set testbody [subst {
-    execsql {$sql}
-    set ::cursorhint
-  }]
-  uplevel [list do_test $tn $testbody [list {*}$hints]]
-  cursorhint_hook
+# Run EXPLAIN on $sql.  Return a list of P5 values for all $opcode
+# opcodes that contain regexp $comment in their comment
+#
+proc p5_of_opcode {db opcode comment sql} {
+  set res {}
+  $db eval "EXPLAIN $sql" x {
+    if {$x(opcode)==$opcode && [regexp $comment $x(comment)]} {
+      lappend res $x(p5)
+    }
+  }
+  return $res
 }
 
+# Verify that when t1 is in the outer loop and t2 is in the inner loop,
+# no cursor hints occur for t1 (since it is a full table scan) but that
+# each t2 access has a cursor hint based on the current t1.a value.
+#
+do_test 1.1 {
+  p4_of_opcode db CursorHint {
+     SELECT * FROM t1 CROSS JOIN t2 WHERE a=x
+  }
+} {/(r*==c0)/}
+do_test 1.2 {
+  p5_of_opcode db OpenRead . {
+     SELECT * FROM t1 CROSS JOIN t2 WHERE a=x
+  }
+} {00 00}
 
-do_cursorhint_test 1.1 {
-  SELECT * FROM t1 CROSS JOIN t2 WHERE a=x;
-} {
-  {(10 == col(0))} 
-  {(20 == col(0))}
-}
+# Do the same test the other way around.
+#
+do_test 2.1 {
+  p4_of_opcode db CursorHint {
+     SELECT * FROM t2 CROSS JOIN t1 WHERE a=x
+  }
+} {/(c0==r*)/}
+do_test 2.2 {
+  p5_of_opcode db OpenRead . {
+     SELECT * FROM t2 CROSS JOIN t1 WHERE a=x
+  }
+} {00 00}
 
-do_cursorhint_test 1.2 {
-  SELECT * FROM t2 CROSS JOIN t1 WHERE a=x;
-} {
-  {(col(0) == 'ten')} 
-  {(col(0) == 'twenty')}
-}
+# Various expressions captured by CursorHint
+#
+do_test 3.1 {
+  p4_of_opcode db CursorHint {
+    SELECT * FROM t1 WHERE a=15 AND c=22 AND rowid!=98
+  }
+} {/(c0==15).*(c2==22).*(rowid!=98)/}
+do_test 3.2 {
+  p4_of_opcode db CursorHint {
+    SELECT * FROM t3 WHERE a<15 AND b>22 AND id!=98
+  }
+} {/(c1<15).*(c2>22).*(c0!=98)/}
 
-do_cursorhint_test 1.3 {
-  SELECT * FROM t1 CROSS JOIN t2 WHERE b=15;
-} {
-  {(col(1) == 15)} 
-}
-
-do_cursorhint_test 1.3 {
-  SELECT * FROM t1 CROSS JOIN t2 WHERE y=b+1;
-} {
-  {(col(1) == (15 + 1))} 
-  {(col(1) == (25 + 1))} 
-}
+# Indexed queries
+#
+do_test 4.1 {
+  db eval {
+    CREATE INDEX t1bc ON t1(b,c);
+    CREATE INDEX t2yz ON t2(y,z);
+  }
+  p4_of_opcode db CursorHint {
+    SELECT * FROM t1 WHERE b>11;
+  }
+} {/(c0>11)/}
+do_test 4.2 {
+  p5_of_opcode db OpenRead . {
+    SELECT * FROM t1 WHERE b>11;
+  }
+} {02 00}
+do_test 4.3 {
+  p4_of_opcode db CursorHint {
+    SELECT c FROM t1 WHERE b>11;
+  }
+} {/(c0>11)/}
+do_test 4.4 {
+  p5_of_opcode db OpenRead . {
+    SELECT c FROM t1 WHERE b>11;
+  }
+} {00}
 
 
 finish_test