Federated Storage Engine, bug 9925 "Federated query processor (step 2 or step 3) not using logic in

WHERE statement"


sql/ha_federated.cc:
  Changes per Jimw's review. 
  
  notes about some suggestions:
  
  1. Tried to replace my_sprintf with strxmov, but had problems. Couldn't 
     get the test suite to run at all, and could not find any particular
     error. Since this is something that is not critical, I'll leave it
     as is for now.
  2. I would like to use my_error to create all of my error messages, but 
     cannot figure out how to get it to take more than one argument to be
     passed to the error message (I tried this once but had errors, and 
     cannot find an example of how to get it to work despite seeing messages
     with obviously more than one arg
  3. Replaced all string building from literals to defined SQL string pieces
     such as "SELECT ", "FROM " ...
  4. Format fixes, spacing fixes completed
  5. Removed records_in_range records calculation functionality
sql/ha_federated.h:
  Formatting changes, new defines for SQL query string tokens
sql/share/errmsg.txt:
  changed 'SRC' to 'SOURCE' per Jimw's review

sql/ha_federated.h

@@ -30,6 +30,42 @@
 #define FEDERATED_QUERY_BUFFER_SIZE STRING_BUFFER_USUAL_SIZE * 5
 #define FEDERATED_RECORDS_IN_RANGE 2
 
+#define FEDERATED_INFO " SHOW TABLE STATUS LIKE "
+#define FEDERATED_SELECT "SELECT "
+#define FEDERATED_WHERE " WHERE "
+#define FEDERATED_FROM " FROM "
+#define FEDERATED_PERCENT "%"
+#define FEDERATED_IS " IS "
+#define FEDERATED_NULL " NULL "
+#define FEDERATED_ISNULL " IS NULL "
+#define FEDERATED_LIKE " LIKE "
+#define FEDERATED_TRUNCATE "TRUNCATE "
+#define FEDERATED_DELETE "DELETE "
+#define FEDERATED_INSERT "INSERT INTO "
+#define FEDERATED_LIMIT1 " LIMIT 1"
+#define FEDERATED_VALUES "VALUES "
+#define FEDERATED_UPDATE "UPDATE "
+#define FEDERATED_SET "SET "
+#define FEDERATED_AND " AND "
+#define FEDERATED_CONJUNCTION ") AND ("
+#define FEDERATED_OR " OR "
+#define FEDERATED_NOT " NOT "
+#define FEDERATED_STAR "* "
+#define FEDERATED_SPACE " "
+#define FEDERATED_SQUOTE "'"
+#define FEDERATED_COMMA ", "
+#define FEDERATED_DQOUTE '"' 
+#define FEDERATED_BTICK  "`" 
+#define FEDERATED_OPENPAREN " ("
+#define FEDERATED_CLOSEPAREN ") "
+#define FEDERATED_NE " != "
+#define FEDERATED_GT " > "
+#define FEDERATED_LT " < "
+#define FEDERATED_LE " <= "
+#define FEDERATED_GE " >= "
+#define FEDERATED_EQ " = "
+#define FEDERATED_1EQ0   " 1=0"
+
 /*
   FEDERATED_SHARE is a structure that will be shared amoung all open handlers
   The example implements the minimum of what you will probably need.
@@ -65,7 +101,7 @@ class ha_federated: public handler
   THR_LOCK_DATA lock;      /* MySQL lock */
   FEDERATED_SHARE *share;    /* Shared lock info */
   MYSQL *mysql; /* MySQL connection */
-  MYSQL_RES *result;
+  MYSQL_RES *stored_result;
   bool scan_flag;
   uint ref_length;
   uint fetch_num; // stores the fetch num
@@ -84,7 +120,7 @@ class ha_federated: public handler
 
 public:
   ha_federated(TABLE *table): handler(table),
-    mysql(0), result(0), scan_flag(0),
+    mysql(0), stored_result(0), scan_flag(0),
     ref_length(sizeof(MYSQL_ROW_OFFSET)), current_position(0)
   {
   }
@@ -145,13 +181,18 @@ class ha_federated: public handler
   double scan_time()
   {
     DBUG_PRINT("info",
-               ("records %d", records)); return (double)(records*1000); 
+               ("records %d", records));
+    return (double)(records*1000); 
   }
   /*
     The next method will never be called if you do not implement indexes.
   */
   double read_time(uint index, uint ranges, ha_rows rows) 
   {
+    /*
+      Per Brian, this number is bugus, but this method must be implemented,
+      and at a later date, he intends to document this issue for handler code
+    */
     return (double) rows /  20.0+1;
   }
 
@@ -190,7 +231,7 @@ class ha_federated: public handler
   int rnd_init(bool scan);                                      //required
   int rnd_end();
   int rnd_next(byte *buf);                                      //required
-  int rnd_pos(byte *buf, byte *pos);                           //required
+  int rnd_pos(byte *buf, byte *pos);                            //required
   void position(const byte *record);                            //required
   void info(uint);                                              //required
 

sql/share/errmsg.txt

@@ -5370,11 +5370,11 @@ ER_SCALE_BIGGER_THAN_PRECISION 42000 S1009
         eng "Scale may not be larger than the precision (column '%-.64s')."
 ER_WRONG_LOCK_OF_SYSTEM_TABLE
         eng "You can't combine write-locking of system '%-.64s.%-.64s' table with other tables"
-ER_CONNECT_TO_FOREIGN_DATA_SRC
+ER_CONNECT_TO_FOREIGN_DATA_SOURCE
         eng "Unable to connect to foreign data source - database '%s'!"
-ER_QUERY_ON_FOREIGN_DATA_SRC
+ER_QUERY_ON_FOREIGN_DATA_SOURCE
         eng "There was a problem processing the query on the foreign data source. Data source error: '%-.64s'"
-ER_FOREIGN_DATA_SRC_DOESNT_EXIST
+ER_FOREIGN_DATA_SOURCE_DOESNT_EXIST
         eng "The foreign data source you are trying to reference does not exist. Data source error : '%-.64s'"
 ER_FOREIGN_DATA_STRING_INVALID_CANT_CREATE
         eng "Can't create federated table. The data source connection string '%-.64s' is not in the correct format"