MDEV-7836: ANALYZE FORMAT=JSON should provide info about GROUP/ORDER BY

Provide basic info about sorting/grouping done by the queries.

1 files changed, 62 insertions, 0 deletions

diff --git a/sql/sql_analyze_stmt.cc b/sql/sql_analyze_stmt.cc
new file mode 100644
index 00000000000..4874c33a544
--- /dev/null
+++ b/sql/sql_analyze_stmt.cc
@@ -0,0 +1,62 @@
+/*
+   Copyright (c) 2015 MariaDB Corporation Ab
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+#ifdef USE_PRAGMA_IMPLEMENTATION
+#pragma implementation				// gcc: Class implementation
+#endif
+
+#include <my_global.h>
+#include "sql_priv.h"
+#include "sql_select.h"
+#include "my_json_writer.h"
+
+void Filesort_tracker::print_json(Json_writer *writer)
+{
+  const char *varied_str= "(varied across executions)";
+  writer->add_member("r_loops").add_ll(r_loops);
+  
+  if (r_limit != HA_POS_ERROR)
+  {
+    writer->add_member("r_limit");
+    if (r_limit == 0)
+      writer->add_str(varied_str);
+    else
+      writer->add_ll(rint(r_limit/r_loops));
+  }
+
+  writer->add_member("r_used_priority_queue"); 
+  if (r_used_pq == r_loops)
+    writer->add_bool(true);
+  else if (r_used_pq == 0)
+    writer->add_bool(false);
+  else
+    writer->add_str(varied_str);
+
+  writer->add_member("r_output_rows").add_ll(rint(r_output_rows / r_loops));
+
+  if (sort_passes)
+    writer->add_member("r_sort_passes").add_ll(rint(sort_passes / r_loops));
+
+  if (sort_buffer_size != 0)
+  {
+    writer->add_member("r_buffer_size");
+    if (sort_buffer_size == ulonglong(-1))
+      writer->add_str(varied_str);
+    else
+      writer->add_size(sort_buffer_size);
+  }
+}
+