Improved comments on the new co-routine logic. Fix a C++-ism in the code.

Update test cases to accommodate the more aggressive use of co-routines.

FossilOrigin-Name: 9243e850ae656d16adc8f0e5c4dcf3dcf476312cee192c39c38685fc437ccbbd

test/cast.test

@@ -481,7 +481,7 @@ do_execsql_test cast-9.0 {
   CREATE VIEW v1(c0, c1) AS 
     SELECT CAST(0.0 AS NUMERIC), COUNT(*) OVER () FROM t0;
   SELECT v1.c0 FROM v1, t0 WHERE v1.c0=0; 
-} {0}
+} {0.0}
 
 
 finish_test

test/eqp.test

@@ -94,7 +94,7 @@ do_eqp_test 1.7.1 {
   SELECT * FROM t3 JOIN (SELECT 1)
 } {
   QUERY PLAN
-  |--MATERIALIZE (subquery-xxxxxx)
+  |--CO-ROUTINE (subquery-xxxxxx)
   |  `--SCAN CONSTANT ROW
   |--SCAN (subquery-xxxxxx)
   `--SCAN t3
@@ -103,7 +103,7 @@ do_eqp_test 1.7.2 {
   SELECT * FROM t3 JOIN (SELECT 1) AS v1
 } {
   QUERY PLAN
-  |--MATERIALIZE v1
+  |--CO-ROUTINE v1
   |  `--SCAN CONSTANT ROW
   |--SCAN v1
   `--SCAN t3
@@ -112,7 +112,7 @@ do_eqp_test 1.7.3 {
   SELECT * FROM t3 AS xx JOIN (SELECT 1) AS yy
 } {
   QUERY PLAN
-  |--MATERIALIZE yy
+  |--CO-ROUTINE yy
   |  `--SCAN CONSTANT ROW
   |--SCAN yy
   `--SCAN xx
@@ -123,7 +123,7 @@ do_eqp_test 1.8 {
   SELECT * FROM t3 JOIN (SELECT 1 UNION SELECT 2)
 } {
   QUERY PLAN
-  |--MATERIALIZE (subquery-xxxxxx)
+  |--CO-ROUTINE (subquery-xxxxxx)
   |  `--COMPOUND QUERY
   |     |--LEFT-MOST SUBQUERY
   |     |  `--SCAN CONSTANT ROW
@@ -136,7 +136,7 @@ do_eqp_test 1.9 {
   SELECT * FROM t3 JOIN (SELECT 1 EXCEPT SELECT a FROM t3 LIMIT 17) AS abc
 } {
   QUERY PLAN
-  |--MATERIALIZE abc
+  |--CO-ROUTINE abc
   |  `--COMPOUND QUERY
   |     |--LEFT-MOST SUBQUERY
   |     |  `--SCAN CONSTANT ROW
@@ -149,7 +149,7 @@ do_eqp_test 1.10 {
   SELECT * FROM t3 JOIN (SELECT 1 INTERSECT SELECT a FROM t3 LIMIT 17) AS abc
 } {
   QUERY PLAN
-  |--MATERIALIZE abc
+  |--CO-ROUTINE abc
   |  `--COMPOUND QUERY
   |     |--LEFT-MOST SUBQUERY
   |     |  `--SCAN CONSTANT ROW
@@ -163,7 +163,7 @@ do_eqp_test 1.11 {
   SELECT * FROM t3 JOIN (SELECT 1 UNION ALL SELECT a FROM t3 LIMIT 17) abc
 } {
   QUERY PLAN
-  |--MATERIALIZE abc
+  |--CO-ROUTINE abc
   |  `--COMPOUND QUERY
   |     |--LEFT-MOST SUBQUERY
   |     |  `--SCAN CONSTANT ROW
@@ -295,7 +295,7 @@ det 3.2.2 {
   ORDER BY x2.y LIMIT 5
 } {
   QUERY PLAN
-  |--MATERIALIZE x1
+  |--CO-ROUTINE x1
   |  |--SCAN t1
   |  `--USE TEMP B-TREE FOR ORDER BY
   |--MATERIALIZE x2
@@ -834,7 +834,7 @@ do_eqp_test 9.1 {
   ORDER BY 1;
 } {
   QUERY PLAN
-  |--MATERIALIZE thread
+  |--CO-ROUTINE thread
   |  |--SCAN x USING INDEX forumthread
   |  |--USING ROWID SEARCH ON TABLE private FOR IN-OPERATOR
   |  |--CORRELATED SCALAR SUBQUERY xxxxxx

test/with3.test

@@ -89,7 +89,7 @@ ifcapable analyze {
     SELECT * FROM cnt, y1 WHERE i=a
   } [string map {"\n  " \n} {
     QUERY PLAN
-    |--MATERIALIZE cnt
+    |--CO-ROUTINE cnt
     |  |--SETUP
     |  |  `--SCAN CONSTANT ROW
     |  `--RECURSIVE STEP
@@ -103,7 +103,7 @@ ifcapable analyze {
     SELECT * FROM cnt, y1 WHERE i=a
   } [string map {"\n  " \n} {
     QUERY PLAN
-    |--MATERIALIZE cnt
+    |--CO-ROUTINE cnt
     |  |--SETUP
     |  |  `--SCAN CONSTANT ROW
     |  `--RECURSIVE STEP
@@ -125,7 +125,7 @@ do_eqp_test 3.2.2 {
      WHERE c.id=w2.pk AND c.id=w1.pk;
 } {
   QUERY PLAN
-  |--MATERIALIZE c
+  |--CO-ROUTINE c
   |  |--SETUP
   |  |  |--SCAN CONSTANT ROW
   |  |  `--SCALAR SUBQUERY xxxxxx

test/with6.test

@@ -87,7 +87,7 @@ do_eqp_test 131 {
          (SELECT x FROM c LIMIT 5) AS c3;
 } {
   QUERY PLAN
-  |--MATERIALIZE c1
+  |--CO-ROUTINE c1
   |  |--CO-ROUTINE c
   |  |  `--SCAN 2 CONSTANT ROWS
   |  `--SCAN c
@@ -123,7 +123,7 @@ do_eqp_test 141 {
          (SELECT x FROM c LIMIT 7) AS c3;
 } {
   QUERY PLAN
-  |--MATERIALIZE c1
+  |--CO-ROUTINE c1
   |  |--MATERIALIZE c
   |  |  `--SCAN 2 CONSTANT ROWS
   |  `--SCAN c
@@ -151,7 +151,7 @@ do_eqp_test 151 {
          (SELECT x FROM c LIMIT 7) AS c3;
 } {
   QUERY PLAN
-  |--MATERIALIZE c1
+  |--CO-ROUTINE c1
   |  |--MATERIALIZE c
   |  |  `--SCAN 2 CONSTANT ROWS
   |  `--SCAN c
@@ -228,7 +228,7 @@ do_eqp_test 211 {
   SELECT y FROM t2 ORDER BY y;
 } {
   QUERY PLAN
-  |--MATERIALIZE c1
+  |--CO-ROUTINE c1
   |  |--CO-ROUTINE c
   |  |  `--SCAN 3 CONSTANT ROWS
   |  `--SCAN c