WL#1727 Implement read_range_first and read_range_next

sql/ha_ndbcluster.cc:
  Added new function set_bounds, used to set bounds in NDB from a key_range
  Updated ordered_index_scan to take start_key and end_key as parameters
  Override of functions read_range_first and read_range_next, to call appropriate access function in NDB
sql/ha_ndbcluster.h:
  Added functions set_bounds, read_range_first and read_range_next
  Changed declaration of ordered_index_scan

1 files changed, 127 insertions, 80 deletions

diff --git a/sql/ha_ndbcluster.cc b/sql/ha_ndbcluster.cc
index 3bc322878d1..5d5bfdaaee8 100644
--- a/sql/ha_ndbcluster.cc
+++ b/sql/ha_ndbcluster.cc
@@ -635,24 +635,79 @@ inline int ha_ndbcluster::next_result(byte *buf)
 
 
 /*
+  Set bounds for a ordered index scan, use key_range
+*/
+
+int ha_ndbcluster::set_bounds(NdbOperation *op,
+			      const key_range *key,
+			      int bound)
+{
+  uint i, tot_len;
+  byte *key_ptr;
+  KEY* key_info= table->key_info + active_index;
+  KEY_PART_INFO* key_part= key_info->key_part;
+  KEY_PART_INFO* end= key_part+key_info->key_parts;
+
+  DBUG_ENTER("set_bounds");
+  DBUG_PRINT("enter", ("bound: %d", bound));
+  DBUG_PRINT("enter", ("key_parts: %d", key_info->key_parts));
+  DBUG_PRINT("enter", ("key->length: %d", key->length));
+  DBUG_PRINT("enter", ("key->flag: %d", key->flag));
+
+  // Set bounds using key data
+  tot_len= 0;
+  key_ptr= (byte *) key->key;    
+  for (; key_part != end; key_part++)
+  {
+    Field* field= key_part->field;
+    uint32 field_len=  field->pack_length();
+    tot_len+= field_len;
+
+    const char* bounds[]= {"LE", "LT", "GE", "GT", "EQ"};
+    DBUG_ASSERT(bound >= 0 && bound <= 4);    
+    DBUG_PRINT("info", ("Set Bound%s on %s", 
+			bounds[bound],
+			field->field_name));
+    DBUG_DUMP("key", (char*)key_ptr, field_len);
+
+    if (op->setBound(field->field_name,
+		     bound, 
+		     key_ptr,
+		     field_len) != 0)
+      ERR_RETURN(op->getNdbError());
+    
+    key_ptr+= field_len;
+    
+    if (tot_len >= key->length)
+      break;
+
+    /*
+      Only one bound which is not EQ can be set
+      so if this bound was not EQ, bail out and make 
+      a best effort attempt
+    */
+    if (bound != NdbOperation::BoundEQ)
+      break;
+  }
+
+  DBUG_RETURN(0);
+}
+
+
+/*
   Read record(s) from NDB using ordered index scan
 */
 
-int ha_ndbcluster::ordered_index_scan(const byte *key, uint key_len, 
-				      byte *buf,
-				      enum ha_rkey_function find_flag)
+int ha_ndbcluster::ordered_index_scan(const key_range *start_key,
+				      const key_range *end_key,
+				      bool sorted, byte* buf)
 {  
   uint no_fields= table->fields;
-  uint tot_len, i;
+  uint i;
   NdbConnection *trans= m_active_trans;
   NdbResultSet *cursor= m_active_cursor;
   NdbScanOperation *op;
-  const char *bound_str= NULL;
   const char *index_name;
-  NdbOperation::BoundType bound_type = NdbOperation::BoundEQ;
-  bool can_be_handled_by_ndb= FALSE;
-  byte *key_ptr;
-  KEY *key_info;
   THD* thd = current_thd;
   DBUG_ENTER("ordered_index_scan");
   DBUG_PRINT("enter", ("index: %u", active_index));  
@@ -664,77 +719,27 @@ int ha_ndbcluster::ordered_index_scan(const byte *key, uint key_len,
   if (!(cursor= op->readTuples(parallelism)))
     ERR_RETURN(trans->getNdbError());
   m_active_cursor= cursor;
-  
-  switch (find_flag) {
-  case HA_READ_KEY_EXACT: /* Find first record else error */
-    bound_str= "HA_READ_KEY_EXACT";
-    bound_type= NdbOperation::BoundEQ;
-    can_be_handled_by_ndb= TRUE;
-    break;
-  case HA_READ_KEY_OR_NEXT: /* Record or next record */
-    bound_str= "HA_READ_KEY_OR_NEXT";
-    bound_type= NdbOperation::BoundLE;
-    can_be_handled_by_ndb= TRUE;
-    break;
-  case HA_READ_KEY_OR_PREV: /* Record or previous */
-    bound_str= "HA_READ_KEY_OR_PREV";
-    bound_type= NdbOperation::BoundGE;
-    can_be_handled_by_ndb= TRUE;
-    break;
-  case HA_READ_AFTER_KEY: /* Find next rec. after key-record */
-    bound_str= "HA_READ_AFTER_KEY";
-    bound_type= NdbOperation::BoundLT;
-    can_be_handled_by_ndb= TRUE;
-    break;
-  case HA_READ_BEFORE_KEY: /* Find next rec. before key-record */
-    bound_str= "HA_READ_BEFORE_KEY";
-    bound_type= NdbOperation::BoundGT;
-    can_be_handled_by_ndb= TRUE;
-    break;
-  case HA_READ_PREFIX: /* Key which as same prefix */
-    bound_str= "HA_READ_PREFIX";
-    break;
-  case HA_READ_PREFIX_LAST: /* Last key with the same prefix */
-    bound_str= "HA_READ_PREFIX_LAST";
-    break;
-  case HA_READ_PREFIX_LAST_OR_PREV: 
-    /* Last or prev key with the same prefix */
-    bound_str= "HA_READ_PREFIX_LAST_OR_PREV";
-    break;
-  default:
-    bound_str= "UNKNOWN";
-    break;
-  }
-  DBUG_PRINT("info", ("find_flag: %s, bound_type: %d,"
-		      "can_be_handled_by_ndb: %d", 
-		      bound_str, bound_type, can_be_handled_by_ndb));    
-  if (!can_be_handled_by_ndb)
+
+  if (start_key && 
+      set_bounds(op, start_key, 
+		 (start_key->flag == HA_READ_KEY_EXACT) ? 
+		 NdbOperation::BoundEQ :
+		 (start_key->flag == HA_READ_AFTER_KEY) ? 
+		 NdbOperation::BoundLT : 
+		 NdbOperation::BoundLE))
     DBUG_RETURN(1);
+
+  if (end_key &&  
+      (start_key && start_key->flag != HA_READ_KEY_EXACT) &&
+      // MASV Is it a bug that end_key is not 0 
+      // if start flag is HA_READ_KEY_EXACT
       
-  // Set bounds using key data
-  tot_len= 0;
-  key_ptr= (byte *) key;    
-  key_info= table->key_info + active_index;
-  for (i= 0; i < key_info->key_parts; i++)
-  {
-    Field* field= key_info->key_part[i].field;
-    uint32 field_len=  field->pack_length();
-    DBUG_PRINT("info", ("Set index bound on %s", 
-			field->field_name));
-    DBUG_DUMP("key", (char*)key_ptr, field_len);
-    
-    if (op->setBound(field->field_name,
-		     bound_type, 
-		     key_ptr,
-		     field_len) != 0)
-      ERR_RETURN(op->getNdbError());
-    
-    key_ptr+= field_len;
-    tot_len+= field_len;
-    if (tot_len >= key_len)
-      break;
-  }
-    
+      set_bounds(op, end_key, 
+		 (end_key->flag == HA_READ_AFTER_KEY) ? 
+		 NdbOperation::BoundGE : 
+		 NdbOperation::BoundGT))
+    DBUG_RETURN(1);
+
   // Define attributes to read
   for (i= 0; i < no_fields; i++) 
   {
@@ -1360,9 +1365,13 @@ int ha_ndbcluster::index_read(byte *buf,
   case UNIQUE_INDEX:
     error= unique_index_read(key, key_len, buf);
     break;
-    
+
   case ORDERED_INDEX:
-    error= ordered_index_scan(key, key_len, buf, find_flag);
+    key_range start_key;
+    start_key.key=    key;
+    start_key.length= key_len;
+    start_key.flag=   find_flag;
+    error= ordered_index_scan(&start_key, 0, false, buf);
     break;
 
   default:
@@ -1423,6 +1432,44 @@ int ha_ndbcluster::index_last(byte *buf)
 }
 
 
+int ha_ndbcluster::read_range_first(const key_range *start_key,
+				    const key_range *end_key,
+				    bool sorted)
+{
+  int error= 1;
+  DBUG_ENTER("ha_ndbcluster::read_range_first");
+
+  switch (get_index_type(active_index)){    
+  case PRIMARY_KEY_INDEX:
+    error= pk_read(start_key->key, start_key->length, 
+		   table->record[0]);
+    break;
+
+  case UNIQUE_INDEX:
+    error= unique_index_read(start_key->key, start_key->length, 
+			     table->record[0]);
+    break;
+
+  case ORDERED_INDEX:
+    // Start the ordered index scan and fetch the first row
+    error= ordered_index_scan(start_key, end_key, sorted,
+			      table->record[0]);
+    break;
+
+  default:
+  case UNDEFINED_INDEX:
+    break;
+  }
+  DBUG_RETURN(error);
+}
+
+int ha_ndbcluster::read_range_next(bool eq_range)
+{
+  DBUG_ENTER("ha_ndbcluster::read_range_next");
+  DBUG_RETURN(next_result(table->record[0]));
+}
+
+
 int ha_ndbcluster::rnd_init(bool scan)
 {
   NdbResultSet *cursor= m_active_cursor;