Merge bb-10.1-explain-json into 10.1

4 files changed, 38 insertions, 5 deletions

diff --git a/sql/my_json_writer.cc b/sql/my_json_writer.cc
index 4f933583347..7a3dc776093 100644
--- a/sql/my_json_writer.cc
+++ b/sql/my_json_writer.cc
@@ -218,7 +218,8 @@ bool Single_line_formatting_helper::on_start_array()
   }
   else
   {
-    state= INACTIVE;
+    if (state != DISABLED)
+      state= INACTIVE;
     // TODO: what if we have accumulated some stuff already? shouldn't we
     // flush it?
     return false; // not handled
@@ -313,6 +314,9 @@ void Single_line_formatting_helper::flush_on_one_line()
 
 void Single_line_formatting_helper::disable_and_flush()
 {
+  if (state == DISABLED)
+    return;
+
   bool start_array= (state == IN_ARRAY);
   state= DISABLED;
   // deactivate ourselves and flush all accumulated calls.
diff --git a/sql/sql_explain.cc b/sql/sql_explain.cc
index 800f2ce309b..c68f86ce72c 100644
--- a/sql/sql_explain.cc
+++ b/sql/sql_explain.cc
@@ -27,6 +27,8 @@ const char * STR_DELETING_ALL_ROWS= "Deleting all rows";
 const char * STR_IMPOSSIBLE_WHERE= "Impossible WHERE";
 const char * STR_NO_ROWS_AFTER_PRUNING= "No matching rows after partition pruning";
 
+static void write_item(Json_writer *writer, Item *item);
+
 Explain_query::Explain_query(THD *thd_arg, MEM_ROOT *root) : 
   mem_root(root), upd_del_plan(NULL),  insert_plan(NULL),
   unions(root), selects(root),  thd(thd_arg), apc_enabled(false),
@@ -732,7 +734,17 @@ void Explain_select::print_explain_json(Explain_query *query,
          Explain_basic_join does not have ORDER/GROUP.
          A: factor out join tab printing loop into a common func.
     */
-    Explain_basic_join::print_explain_json(query, writer, is_analyze);
+    writer->add_member("query_block").start_object();
+    writer->add_member("select_id").add_ll(select_id);
+    
+    if (exec_const_cond)
+    {
+      writer->add_member("const_condition");
+      write_item(writer, exec_const_cond);
+    }
+
+    Explain_basic_join::print_explain_json_interns(query, writer, is_analyze);
+    writer->end_object();
   }
 
 }
@@ -742,10 +754,20 @@ void Explain_basic_join::print_explain_json(Explain_query *query,
                                             Json_writer *writer, 
                                             bool is_analyze)
 {
-  Json_writer_nesting_guard guard(writer);
-
   writer->add_member("query_block").start_object();
   writer->add_member("select_id").add_ll(select_id);
+  
+  print_explain_json_interns(query, writer, is_analyze);
+
+  writer->end_object();
+}
+
+
+void Explain_basic_join::print_explain_json_interns(Explain_query *query, 
+                                                    Json_writer *writer, 
+                                                    bool is_analyze)
+{
+  Json_writer_nesting_guard guard(writer);
   for (uint i=0; i< n_join_tabs; i++)
   {
     if (join_tabs[i]->start_dups_weedout)
@@ -757,7 +779,6 @@ void Explain_basic_join::print_explain_json(Explain_query *query,
       writer->end_object();
   }
   print_explain_json_for_children(query, writer, is_analyze);
-  writer->end_object();
 }
 
 
diff --git a/sql/sql_explain.h b/sql/sql_explain.h
index a7ef0beb649..c4bfa4d09bf 100644
--- a/sql/sql_explain.h
+++ b/sql/sql_explain.h
@@ -175,6 +175,9 @@ public:
   void print_explain_json(Explain_query *query, Json_writer *writer, 
                           bool is_analyze);
 
+  void print_explain_json_interns(Explain_query *query, Json_writer *writer,
+                                  bool is_analyze);
+
   /* A flat array of Explain structs for tables. */
   Explain_table_access** join_tabs;
   uint n_join_tabs;
@@ -222,6 +225,9 @@ public:
   */
   const char *message;
   
+  /* Expensive constant condition */
+  Item *exec_const_cond;
+  
   /* Global join attributes. In tabular form, they are printed on the first row */
   bool using_temporary;
   bool using_filesort;
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index a1231152254..cbb5868623c 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -23768,6 +23768,8 @@ int JOIN::save_explain_data_intern(Explain_query *output, bool need_tmp_table,
     if (need_order)
       xpl_sel->using_filesort= true;
 
+    xpl_sel->exec_const_cond= exec_const_cond;
+
     JOIN_TAB* const first_top_tab= first_breadth_first_tab(join, WALK_OPTIMIZATION_TABS);
     JOIN_TAB* prev_bush_root_tab= NULL;