Merge branch 'mysql-8.0' into mysql-trunk

Change-Id: Iac8f3ded05b85a809d92f7c23c3dc3379c05d611

Author: kahatlen

mysql-test/r/subplan_tokens.result

@@ -6,41 +6,41 @@ test.t1	analyze	status	OK
 SET DEBUG='+d,subplan_tokens';
 EXPLAIN FORMAT=tree SELECT * FROM t1;
 EXPLAIN
--> [0x383f9723be72015d] Table scan on t1  (cost=0.08..0.25 rows=3)
+-> [0xeed2c0bd3e39ba93] Table scan on t1  (cost=0.08..0.25 rows=3)
 
 To force this plan, use:
-SET DEBUG='+d,subplan_tokens,force_subplan_0x383f9723be72015d';
+SET DEBUG='+d,subplan_tokens,force_subplan_0xeed2c0bd3e39ba93';
 
 EXPLAIN FORMAT=tree SELECT * FROM t1 ORDER BY a;
 EXPLAIN
--> [0x4f56594d4fd521c9] Index scan on t1 using a  (cost=0.08..0.25 rows=3)
+-> [0x2215d3ce44f01b0d] Index scan on t1 using a  (cost=0.08..0.25 rows=3)
 
 To force this plan, use:
-SET DEBUG='+d,subplan_tokens,force_subplan_0x4f56594d4fd521c9';
+SET DEBUG='+d,subplan_tokens,force_subplan_0x2215d3ce44f01b0d';
 
-SET DEBUG='+d,subplan_tokens,force_subplan_0x383f9723be72015d';
+SET DEBUG='+d,subplan_tokens,force_subplan_0xeed2c0bd3e39ba93';
 EXPLAIN FORMAT=tree SELECT * FROM t1 ORDER BY a;
 EXPLAIN
--> [0x685afbd3f088dc87] Sort: t1.a  (cost=1.03..1.03 rows=3)
-    -> [0x383f9723be72015d] Table scan on t1  (cost=0.08..0.25 rows=3)
+-> [0xd3135ef8a92cb9b8] Sort: t1.a  (cost=1.03..1.03 rows=3)
+    -> [0xeed2c0bd3e39ba93] Table scan on t1  (cost=0.08..0.25 rows=3)
 
 To force this plan, use:
-SET DEBUG='+d,subplan_tokens,force_subplan_0x685afbd3f088dc87,force_subplan_0x383f9723be72015d';
+SET DEBUG='+d,subplan_tokens,force_subplan_0xd3135ef8a92cb9b8,force_subplan_0xeed2c0bd3e39ba93';
 
 SET DEBUG='+d,subplan_tokens,'
-  'force_subplan_0x90b6f02248424220,'
-  'force_subplan_0x383f9723be72015d,'
-  'force_subplan_0xedd60db81c76aaf5';
+  'force_subplan_0x38d170e70c04e92c,'
+  'force_subplan_0xeed2c0bd3e39ba93,'
+  'force_subplan_0x079e429c703ec298';
 EXPLAIN FORMAT=tree SELECT * FROM t1 JOIN t1 AS t2 ON t1.a=t2.a ORDER BY t1.a;
 EXPLAIN
--> [0x9fe1924c5f48742c] Sort: t1.a  (cost=2.09..2.09 rows=3)
-    -> [0x90b6f02248424220] Inner hash join (t1.a = t2.a)  (cost=0.80..1.31 rows=3)
-        -> [0x383f9723be72015d] Table scan on t1  (cost=0.08..0.25 rows=3)
+-> [0x1836646581797f8f] Sort: t1.a  (cost=2.09..2.09 rows=3)
+    -> [0x38d170e70c04e92c] Inner hash join (t1.a = t2.a)  (cost=0.80..1.31 rows=3)
+        -> [0xeed2c0bd3e39ba93] Table scan on t1  (cost=0.08..0.25 rows=3)
         -> Hash
-            -> [0xedd60db81c76aaf5] Table scan on t2  (cost=0.08..0.25 rows=3)
+            -> [0x079e429c703ec298] Table scan on t2  (cost=0.08..0.25 rows=3)
 
 To force this plan, use:
-SET DEBUG='+d,subplan_tokens,force_subplan_0x9fe1924c5f48742c,force_subplan_0x90b6f02248424220,force_subplan_0x383f9723be72015d,force_subplan_0xedd60db81c76aaf5';
+SET DEBUG='+d,subplan_tokens,force_subplan_0x1836646581797f8f,force_subplan_0x38d170e70c04e92c,force_subplan_0xeed2c0bd3e39ba93,force_subplan_0x079e429c703ec298';
 
 SET DEBUG='-d,subplan_tokens';
 EXPLAIN FORMAT=tree SELECT * FROM t1 JOIN t1 AS t2 ON t1.a=t2.a ORDER BY t1.a;

mysql-test/t/subplan_tokens.test

@@ -14,16 +14,16 @@ EXPLAIN FORMAT=tree SELECT * FROM t1 ORDER BY a;
 
 # However, if we force the table scan variant from earlier,
 # we should get a sort instead.
-SET DEBUG='+d,subplan_tokens,force_subplan_0x383f9723be72015d';
+SET DEBUG='+d,subplan_tokens,force_subplan_0xeed2c0bd3e39ba93';
 EXPLAIN FORMAT=tree SELECT * FROM t1 ORDER BY a;
 
-# Force a hash join; this is the truncated MD5 checksum of:
-# Inner hash join (t1.a = t2.a),0x383f9723be72015d,Hash:0xedd60db81c76aaf5
+# Force a hash join; this is the truncated SHA-256 checksum of:
+# Inner hash join (t1.a = t2.a),0xeed2c0bd3e39ba93,Hash:0x079e429c703ec298
 # We also force the hash join subplans to ensure they are not optimized away.
 SET DEBUG='+d,subplan_tokens,'
-  'force_subplan_0x90b6f02248424220,'
-  'force_subplan_0x383f9723be72015d,'
-  'force_subplan_0xedd60db81c76aaf5';
+  'force_subplan_0x38d170e70c04e92c,'
+  'force_subplan_0xeed2c0bd3e39ba93,'
+  'force_subplan_0x079e429c703ec298';
 EXPLAIN FORMAT=tree SELECT * FROM t1 JOIN t1 AS t2 ON t1.a=t2.a ORDER BY t1.a;
 
 # When not forcing anything, we should prefer the nested loop join.

sql/join_optimizer/access_path.cc

@@ -1091,8 +1091,12 @@ unique_ptr_destroy_only<RowIterator> CreateIteratorFromAccessPath(
       }
       case AccessPath::DELETE_ROWS: {
         const auto &param = path->delete_rows();
-        SetUpTablesForDelete(thd, join);
         if (job.children.is_null()) {
+          // Setting up tables for delete must be done before the child
+          // iterators are created, as some of the child iterators need to see
+          // the final read set when they are constructed, so doing it in
+          // DeleteRowsIterator's constructor or Init() is too late.
+          SetUpTablesForDelete(thd, join);
           SetupJobsForChildren(mem_root, param.child, join,
                                eligible_for_batch_mode, &job, &todo);
           continue;

sql/join_optimizer/explain_access_path.cc

@@ -22,8 +22,13 @@
 
 #include "sql/join_optimizer/explain_access_path.h"
 
-#include "my_md5.h"
-#include "my_md5_size.h"
+#include <functional>
+#include <string>
+#include <vector>
+
+#include <openssl/sha.h>
+
+#include "sha2.h"
 #include "sql/filesort.h"
 #include "sql/item_sum.h"
 #include "sql/iterators/basic_row_iterators.h"
@@ -42,10 +47,7 @@
 #include "sql/range_optimizer/range_optimizer.h"
 #include "sql/sql_optimizer.h"
 #include "sql/table.h"
-
-#include <functional>
-#include <string>
-#include <vector>
+#include "template_utils.h"
 
 using std::string;
 using std::vector;
@@ -1172,7 +1174,7 @@ string PrintQueryPlan(int level, AccessPath *path, JOIN *join,
 }
 
 // 0x
-// truncated_md5(desc1,desc2,...,[child1_desc:]0xchild1,[child2_desc:]0xchild2,...)
+// truncated_sha256(desc1,desc2,...,[child1_desc:]0xchild1,[child2_desc:]0xchild2,...)
 string GetForceSubplanToken(AccessPath *path, JOIN *join) {
   if (path == nullptr) {
     return "";
@@ -1194,13 +1196,14 @@ string GetForceSubplanToken(AccessPath *path, JOIN *join) {
     digest += GetForceSubplanToken(child.path, join);
   }
 
-  unsigned char md5sum[MD5_HASH_SIZE];
-  compute_md5_hash(pointer_cast<char *>(md5sum), digest.data(), digest.size());
+  unsigned char sha256sum[SHA256_DIGEST_LENGTH];
+  (void)SHA_EVP256(pointer_cast<const unsigned char *>(digest.data()),
+                   digest.size(), sha256sum);
 
   char ret[8 * 2 + 2 + 1];
-  snprintf(ret, sizeof(ret), "0x%02x%02x%02x%02x%02x%02x%02x%02x", md5sum[0],
-           md5sum[1], md5sum[2], md5sum[3], md5sum[4], md5sum[5], md5sum[6],
-           md5sum[7]);
+  snprintf(ret, sizeof(ret), "0x%02x%02x%02x%02x%02x%02x%02x%02x", sha256sum[0],
+           sha256sum[1], sha256sum[2], sha256sum[3], sha256sum[4], sha256sum[5],
+           sha256sum[6], sha256sum[7]);
 
   return ret;
 }

sql/join_optimizer/explain_access_path.h

@@ -1,4 +1,4 @@
-/* Copyright (c) 2020, 2021, Oracle and/or its affiliates.
+/* Copyright (c) 2020, 2022, Oracle and/or its affiliates.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License, version 2.0,
@@ -51,7 +51,7 @@ std::string PrintQueryPlan(
   preferred over all others.
 
   The token returned is “0x<digest>”, where <digest> is the first 64 bits
-  of the MD5 sum of this string:
+  of the SHA-256 sum of this string:
 
     desc1,desc2,...,[child1_desc:]0xchild1,[child2_desc:]0xchild2,<more
   children>
@@ -60,7 +60,7 @@ std::string PrintQueryPlan(
   and 0xchild1 is the token for children. The normal way to generate such
   tokens is to use SET DEBUG='+d,subplan_tokens' and look at the EXPLAIN
   FORMAT=tree, but in a pinch, you can also write them by hand and use
-  md5sum or a similar tool.
+  sha256sum or a similar tool.
 
   Only the hypergraph join optimizer honors token preferences, but EXPLAIN
   FORMAT=tree shows computed tokens for both optimizers.