Cleanup: fake_select_lex->select_number=FAKE_SELECT_LEX_ID, not [U]INT_MAX

SELECT_LEX objects that are "fake_select_lex" (i.e read UNION output)
used both INT_MAX and UINT_MAX as select_number.
- mysql_explain_union() assigned UINT_MAX
- st_select_lex_unit::add_fake_select_lex assigned INT_MAX

This didn't matter initially (before EXPLAIN FORMAT=JSON), because the
code  had no checks for this value.

EXPLAIN FORMAT=JSON and later other features did introduce checks for
select_number values. The check had to check for two constants and
looked really confusing.

This patch joins the two constants into one - FAKE_SELECT_LEX_ID.

1 files changed, 8 insertions, 8 deletions

diff --git a/sql/sql_explain.h b/sql/sql_explain.h
index 9090416847f..42590e0bea0 100644
--- a/sql/sql_explain.h
+++ b/sql/sql_explain.h
@@ -74,7 +74,7 @@ class Json_writer;
 *************************************************************************************/
 
 
-const int FAKE_SELECT_LEX_ID= (int)UINT_MAX;
+const uint FAKE_SELECT_LEX_ID= UINT_MAX;
 
 class Explain_query;
 
@@ -108,7 +108,7 @@ public:
   };
 
   virtual enum explain_node_type get_type()= 0;
-  virtual int get_select_id()= 0;
+  virtual uint get_select_id()= 0;
 
   /**
     expression cache statistics
@@ -166,9 +166,9 @@ public:
 
   bool add_table(Explain_table_access *tab, Explain_query *query);
 
-  int get_select_id() { return select_id; }
+  uint get_select_id() { return select_id; }
 
-  int select_id;
+  uint select_id;
 
   int print_explain(Explain_query *query, select_result_sink *output,
                     uint8 explain_flags, bool is_analyze);
@@ -352,7 +352,7 @@ public:
   enum explain_node_type get_type() { return EXPLAIN_UNION; }
   unit_common_op operation;
 
-  int get_select_id()
+  uint get_select_id()
   {
     DBUG_ASSERT(union_members.elements() > 0);
     return union_members.at(0);
@@ -879,7 +879,7 @@ public:
   {}
 
   virtual enum explain_node_type get_type() { return EXPLAIN_UPDATE; }
-  virtual int get_select_id() { return 1; /* always root */ }
+  virtual uint get_select_id() { return 1; /* always root */ }
 
   const char *select_type;
 
@@ -959,7 +959,7 @@ public:
   StringBuffer<64> table_name;
 
   enum explain_node_type get_type() { return EXPLAIN_INSERT; }
-  int get_select_id() { return 1; /* always root */ }
+  uint get_select_id() { return 1; /* always root */ }
 
   int print_explain(Explain_query *query, select_result_sink *output, 
                     uint8 explain_flags, bool is_analyze);
@@ -986,7 +986,7 @@ public:
   bool deleting_all_rows;
 
   virtual enum explain_node_type get_type() { return EXPLAIN_DELETE; }
-  virtual int get_select_id() { return 1; /* always root */ }
+  virtual uint get_select_id() { return 1; /* always root */ }
 
   virtual int print_explain(Explain_query *query, select_result_sink *output, 
                             uint8 explain_flags, bool is_analyze);