bk commit into 5.1 tree (mskold:1.2320) BUG#21507

[Martin Skold]

Below is the list of changes that have just been committed into a local
5.1 repository of marty. When marty does a push these changes will
be propagated to the main repository and, within 24 hours after the
push, to the public repository.
For information on how to access the public repository
see http://dev.mysql.com/doc/mysql/en/installing-source-tree.html

ChangeSet@stripped, 2006-11-13 12:56:45+01:00, mskold@stripped +3 -0
  bug#21507 I can't create a unique hash index in NDB: Added possibillity to create hash
only indexes with NULL valued attributes, but any NULL valued access will become full
table scan with pushed condition on index attribute values. 5.1 re-implementation

  mysql-test/r/ndb_index_unique.result@stripped, 2006-11-13 12:56:16+01:00, mskold@stripped
+34 -1
    bug#21507 I can't create a unique hash index in NDB: Added possibillity to create hash
only indexes with NULL valued attributes, but any NULL valued access will become full
table scan with pushed condition on index attribute values. 5.1 re-implementation

  sql/ha_ndbcluster.cc@stripped, 2006-11-13 12:56:16+01:00, mskold@stripped +213 -35
    bug#21507 I can't create a unique hash index in NDB: Added possibillity to create hash
only indexes with NULL valued attributes, but any NULL valued access will become full
table scan with pushed condition on index attribute values. 5.1 re-implementation

  sql/ha_ndbcluster.h@stripped, 2006-11-13 12:56:15+01:00, mskold@stripped +19 -3
    bug#21507 I can't create a unique hash index in NDB: Added possibillity to create hash
only indexes with NULL valued attributes, but any NULL valued access will become full
table scan with pushed condition on index attribute values. 5.1 re-implementation

# This is a BitKeeper patch.  What follows are the unified diffs for the
# set of deltas contained in the patch.  The rest of the patch, the part
# that BitKeeper cares about, is below these diffs.
# User:	mskold
# Host:	linux.site
# Root:	/windows/Linux_space/MySQL/mysql-5.1-new-ndb

--- 1.30/mysql-test/r/ndb_index_unique.result	2006-11-13 12:56:55 +01:00
+++ 1.31/mysql-test/r/ndb_index_unique.result	2006-11-13 12:56:55 +01:00
@@ -144,7 +144,40 @@ b int unsigned not null,
 c int unsigned,
 UNIQUE (b, c) USING HASH	
 ) engine=ndbcluster;
-ERROR 42000: Table handler doesn't support NULL in given index. Please change column 'c'
to be NOT NULL or use another handler
+Warnings:
+Warning	1121	Ndb does not support unique index on NULL valued attributes, index access
with NULL value will become full table scan
+insert t2
values(1,1,NULL),(2,2,2),(3,3,NULL),(4,4,4),(5,5,NULL),(6,6,6),(7,7,NULL),(8,3,NULL),(9,3,NULL);
+select * from t2 where c IS NULL order by a;
+a	b	c
+1	1	NULL
+3	3	NULL
+5	5	NULL
+7	7	NULL
+8	3	NULL
+9	3	NULL
+select * from t2 where b = 3 AND c IS NULL order by a;
+a	b	c
+3	3	NULL
+8	3	NULL
+9	3	NULL
+select * from t2 where (b = 3 OR b = 5) AND c IS NULL order by a;
+a	b	c
+3	3	NULL
+5	5	NULL
+8	3	NULL
+9	3	NULL
+set @old_ecpd = @@session.engine_condition_pushdown;
+set engine_condition_pushdown = true;
+explain select * from t2 where (b = 3 OR b = 5) AND c IS NULL AND a < 9 order by a;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t2	range	PRIMARY,b	PRIMARY	4	NULL	1	Using where with pushed condition
+select * from t2 where (b = 3 OR b = 5) AND c IS NULL AND a < 9 order by a;
+a	b	c
+3	3	NULL
+5	5	NULL
+8	3	NULL
+set engine_condition_pushdown = @old_ecpd;
+drop table t2;
 CREATE TABLE t3 (
 a int unsigned NOT NULL,
 b int unsigned not null,

--- 1.361/sql/ha_ndbcluster.cc	2006-11-13 12:56:55 +01:00
+++ 1.362/sql/ha_ndbcluster.cc	2006-11-13 12:56:55 +01:00
@@ -1254,6 +1254,9 @@ int ha_ndbcluster::open_indexes(Ndb *ndb
         m_index[i].index= m_index[i].unique_index= NULL;
       else
         break;
+    m_index[i].null_in_unique_index= false;
+    if (check_index_fields_not_null(key_info))
+      m_index[i].null_in_unique_index= true;
   }
 
   if (error && !ignore_error)
@@ -1396,7 +1399,7 @@ NDB_INDEX_TYPE ha_ndbcluster::get_index_
           ORDERED_INDEX);
 } 
 
-int ha_ndbcluster::check_index_fields_not_null(KEY* key_info)
+bool ha_ndbcluster::check_index_fields_not_null(KEY* key_info)
 {
   KEY_PART_INFO* key_part= key_info->key_part;
   KEY_PART_INFO* end= key_part+key_info->key_parts;
@@ -1406,14 +1409,10 @@ int ha_ndbcluster::check_index_fields_no
     {
       Field* field= key_part->field;
       if (field->maybe_null())
-      {
-        my_printf_error(ER_NULL_COLUMN_IN_INDEX,ER(ER_NULL_COLUMN_IN_INDEX),
-                        MYF(0),field->field_name);
-        DBUG_RETURN(ER_NULL_COLUMN_IN_INDEX);
-      }
+	DBUG_RETURN(true);
     }
   
-  DBUG_RETURN(0);
+  DBUG_RETURN(false);
 }
 
 void ha_ndbcluster::release_metadata(THD *thd, Ndb *ndb)
@@ -1513,6 +1512,12 @@ inline NDB_INDEX_TYPE ha_ndbcluster::get
   return m_index[idx_no].type;
 }
 
+inline bool ha_ndbcluster::has_null_in_unique_index(uint idx_no) const
+{
+  DBUG_ASSERT(idx_no < MAX_KEY);
+  return m_index[idx_no].null_in_unique_index;
+}
+
 
 /*
   Get the flags for an index
@@ -2433,6 +2438,78 @@ guess_scan_flags(NdbOperation::LockMode 
   return flags;
 }
 
+
+/*
+  Unique index scan in NDB (full table scan with scan filter)
+ */
+
+int ha_ndbcluster::unique_index_scan(const KEY* key_info, 
+				     const byte *key, 
+				     uint key_len,
+				     byte *buf)
+{
+  int res;
+  NdbScanOperation *op;
+  NdbTransaction *trans= m_active_trans;
+  part_id_range part_spec;
+
+  DBUG_ENTER("unique_index_scan");  
+  DBUG_PRINT("enter", ("Starting new scan on %s", m_tabname));
+
+  NdbOperation::LockMode lm=
+    (NdbOperation::LockMode)get_ndb_lock_type(m_lock.type);
+  int flags= guess_scan_flags(lm, m_table, table->read_set);
+  if (!(op=trans->getNdbScanOperation((const NDBTAB *) m_table)) ||
+      op->readTuples(lm, flags, parallelism))
+    ERR_RETURN(trans->getNdbError());
+  m_active_cursor= op;
+
+  if (m_use_partition_function)
+  {
+    part_spec.start_part= 0;
+    part_spec.end_part= m_part_info->get_tot_partitions() - 1;
+    prune_partition_set(table, &part_spec);
+    DBUG_PRINT("info", ("part_spec.start_part = %u, part_spec.end_part = %u",
+                        part_spec.start_part, part_spec.end_part));
+    /*
+      If partition pruning has found no partition in set
+      we can return HA_ERR_END_OF_FILE
+      If partition pruning has found exactly one partition in set
+      we can optimize scan to run towards that partition only.
+    */
+    if (part_spec.start_part > part_spec.end_part)
+    {
+      DBUG_RETURN(HA_ERR_END_OF_FILE);
+    }
+    else if (part_spec.start_part == part_spec.end_part)
+    {
+      /*
+        Only one partition is required to scan, if sorted is required we
+        don't need it any more since output from one ordered partitioned
+        index is always sorted.
+      */
+      m_active_cursor->setPartitionId(part_spec.start_part);
+    }
+    // If table has user defined partitioning
+    // and no primary key, we need to read the partition id
+    // to support ORDER BY queries
+    if ((table_share->primary_key == MAX_KEY) && 
+        (get_ndb_partition_id(op)))
+      ERR_RETURN(trans->getNdbError());
+  }
+
+  if (generate_scan_filter_from_key(op, key_info, key, key_len, buf))
+    DBUG_RETURN(ndb_err(trans));
+  if ((res= define_read_attrs(buf, op)))
+    DBUG_RETURN(res);
+
+  if (execute_no_commit(this,trans,false) != 0)
+    DBUG_RETURN(ndb_err(trans));
+  DBUG_PRINT("exit", ("Scan started successfully"));
+  DBUG_RETURN(next_result(buf));
+}
+
+
 /*
   Start full table scan in NDB
  */
@@ -3396,6 +3473,11 @@ int ha_ndbcluster::read_range_first_to_b
         DBUG_RETURN(error);
       DBUG_RETURN(unique_index_read(start_key->key, start_key->length, buf));
     }
+    else if (type == UNIQUE_INDEX)
+      DBUG_RETURN(unique_index_scan(key_info, 
+				    start_key->key, 
+				    start_key->length, 
+				    buf));
     break;
   default:
     break;
@@ -5014,8 +5096,13 @@ int ha_ndbcluster::create_index(const ch
       error= create_unique_index(unique_name, key_info);
     break;
   case UNIQUE_INDEX:
-    if (!(error= check_index_fields_not_null(key_info)))
-      error= create_unique_index(unique_name, key_info);
+    if (check_index_fields_not_null(key_info))
+    {
+      push_warning_printf(current_thd, MYSQL_ERROR::WARN_LEVEL_WARN,
+			  ER_NULL_COLUMN_IN_INDEX,
+			  "Ndb does not support unique index on NULL valued attributes, index access with NULL
value will become full table scan");
+    }
+    error= create_unique_index(unique_name, key_info);
     break;
   case ORDERED_INDEX:
     error= create_ordered_index(name, key_info);
@@ -7739,6 +7826,30 @@ ha_ndbcluster::release_completed_operati
   trans->releaseCompletedOperations();
 }
 
+bool 
+ha_ndbcluster::null_value_index_search(KEY_MULTI_RANGE *ranges,
+				       KEY_MULTI_RANGE *end_range,
+				       HANDLER_BUFFER *buffer)
+{
+  DBUG_ENTER("null_value_index_search");
+  KEY* key_info= table->key_info + active_index;
+  KEY_MULTI_RANGE *range= ranges;
+  ulong reclength= table->s->reclength;
+  byte *curr= (byte*)buffer->buffer;
+  byte *end_of_buffer= (byte*)buffer->buffer_end;
+  
+  for (; range<end_range && curr+reclength <= end_of_buffer; 
+       range++)
+  {
+    const byte *key= range->start_key.key;
+    uint key_len= range->start_key.length;
+    if (check_null_in_key(key_info, key, key_len))
+      DBUG_RETURN(true);
+    curr += reclength;
+  }
+  DBUG_RETURN(false);
+}
+
 int
 ha_ndbcluster::read_multi_range_first(KEY_MULTI_RANGE **found_range_p,
                                       KEY_MULTI_RANGE *ranges, 
@@ -7756,11 +7867,14 @@ ha_ndbcluster::read_multi_range_first(KE
   NdbOperation* op;
   Thd_ndb *thd_ndb= get_thd_ndb(current_thd);
 
-  if (uses_blob_value())
+  /**
+   * blobs and unique hash index with NULL can't be batched currently
+   */
+  if (uses_blob_value() ||
+      (index_type ==  UNIQUE_INDEX &&
+       has_null_in_unique_index(active_index) &&
+       null_value_index_search(ranges, ranges+range_count, buffer)))
   {
-    /**
-     * blobs can't be batched currently
-     */
     m_disable_multi_read= TRUE;
     DBUG_RETURN(handler::read_multi_range_first(found_range_p, 
                                                 ranges, 
@@ -9712,31 +9826,12 @@ ha_ndbcluster::generate_scan_filter(Ndb_
                                     NdbScanOperation *op)
 {
   DBUG_ENTER("generate_scan_filter");
+
   if (ndb_cond_stack)
   {
-    DBUG_PRINT("info", ("Generating scan filter"));
     NdbScanFilter filter(op);
-    bool multiple_cond= FALSE;
-    // Wrap an AND group around multiple conditions
-    if (ndb_cond_stack->next) {
-      multiple_cond= TRUE;
-      if (filter.begin() == -1)
-        DBUG_RETURN(1); 
-    }
-    for (Ndb_cond_stack *stack= ndb_cond_stack; 
-         (stack); 
-         stack= stack->next)
-      {
-        Ndb_cond *cond= stack->ndb_cond;
-
-        if (build_scan_filter(cond, &filter))
-        {
-          DBUG_PRINT("info", ("build_scan_filter failed"));
-          DBUG_RETURN(1);
-        }
-      }
-    if (multiple_cond && filter.end() == -1)
-      DBUG_RETURN(1);
+    
+    DBUG_RETURN(generate_scan_filter_from_cond(ndb_cond_stack, filter));
   }
   else
   {  
@@ -9745,6 +9840,89 @@ ha_ndbcluster::generate_scan_filter(Ndb_
 
   DBUG_RETURN(0);
 }
+
+int
+ha_ndbcluster::generate_scan_filter_from_cond(Ndb_cond_stack *ndb_cond_stack,
+					      NdbScanFilter& filter)
+{
+  DBUG_ENTER("generate_scan_filter_from_cond");
+  bool multiple_cond= FALSE;
+  
+  DBUG_PRINT("info", ("Generating scan filter"));
+  // Wrap an AND group around multiple conditions
+  if (ndb_cond_stack->next) 
+  {
+    multiple_cond= TRUE;
+    if (filter.begin() == -1)
+      DBUG_RETURN(1); 
+  }
+  for (Ndb_cond_stack *stack= ndb_cond_stack; 
+       (stack); 
+       stack= stack->next)
+  {
+    Ndb_cond *cond= stack->ndb_cond;
+    
+    if (build_scan_filter(cond, &filter))
+    {
+      DBUG_PRINT("info", ("build_scan_filter failed"));
+      DBUG_RETURN(1);
+    }
+  }
+  if (multiple_cond && filter.end() == -1)
+    DBUG_RETURN(1);
+
+  DBUG_RETURN(0);
+}
+
+int ha_ndbcluster::generate_scan_filter_from_key(NdbScanOperation *op,
+						 const KEY* key_info, 
+						 const byte *key, 
+						 uint key_len,
+						 byte *buf)
+{
+  KEY_PART_INFO* key_part= key_info->key_part;
+  KEY_PART_INFO* end= key_part+key_info->key_parts;
+  NdbScanFilter filter(op);
+  int res;
+
+  DBUG_ENTER("generate_scan_filter_from_key");
+  filter.begin(NdbScanFilter::AND);
+  for (; key_part != end; key_part++) 
+  {
+    Field* field= key_part->field;
+    uint32 pack_len= field->pack_length();
+    const byte* ptr= key;
+    char buf[256];
+    DBUG_PRINT("info", ("Filtering value for %s", field->field_name));
+    DBUG_DUMP("key", (char*)ptr, pack_len);
+    if (key_part->null_bit)
+    {
+      DBUG_PRINT("info", ("Generating ISNULL filter"));
+      if (filter.isnull(key_part->fieldnr-1) == -1)
+	DBUG_RETURN(1);
+    }
+    else
+    {
+      DBUG_PRINT("info", ("Generating EQ filter"));
+      if (filter.cmp(NdbScanFilter::COND_EQ, 
+		     key_part->fieldnr-1,
+		     ptr,
+		     pack_len) == -1)
+	DBUG_RETURN(1);
+    }
+    key += key_part->store_length;
+  }      
+  // Add any pushed condition
+  if (m_cond_stack &&
+      (res= generate_scan_filter_from_cond(m_cond_stack, filter)))
+    DBUG_RETURN(res);
+    
+  if (filter.end() == -1)
+    DBUG_RETURN(1);
+
+  DBUG_RETURN(0);
+}
+
 
 /*
   get table space info for SHOW CREATE TABLE

--- 1.156/sql/ha_ndbcluster.h	2006-11-13 12:56:55 +01:00
+++ 1.157/sql/ha_ndbcluster.h	2006-11-13 12:56:55 +01:00
@@ -73,6 +73,7 @@ typedef struct ndb_index_data {
   const NdbDictionary::Index *index;
   const NdbDictionary::Index *unique_index;
   unsigned char *unique_index_attrid_map;
+  bool null_in_unique_index;
   // In this version stats are not shared between threads
   NdbIndexStat* index_stat;
   uint index_stat_cache_entries;
@@ -670,6 +671,9 @@ class ha_ndbcluster: public handler
                              KEY_MULTI_RANGE*ranges, uint range_count,
                              bool sorted, HANDLER_BUFFER *buffer);
   int read_multi_range_next(KEY_MULTI_RANGE **found_range_p);
+  bool null_value_index_search(KEY_MULTI_RANGE *ranges,
+			       KEY_MULTI_RANGE *end_range,
+			       HANDLER_BUFFER *buffer);
 
   bool get_error_message(int error, String *buf);
   ha_rows records();
@@ -814,7 +818,8 @@ private:
   NDB_INDEX_TYPE get_index_type_from_table(uint index_no) const;
   NDB_INDEX_TYPE get_index_type_from_key(uint index_no, KEY *key_info, 
                                          bool primary) const;
-  int check_index_fields_not_null(KEY *key_info);
+  bool has_null_in_unique_index(uint idx_no) const;
+  bool check_index_fields_not_null(KEY *key_info);
 
   uint set_up_partition_info(partition_info *part_info,
                              TABLE *table,
@@ -829,6 +834,12 @@ private:
                          const key_range *end_key,
                          bool sorted, bool descending, byte* buf,
                          part_id_range *part_spec);
+  int unique_index_read(const byte *key, uint key_len, 
+                        byte *buf);
+  int unique_index_scan(const KEY* key_info, 
+			const byte *key, 
+			uint key_len,
+			byte *buf);
   int full_table_scan(byte * buf);
 
   bool check_all_operations_for_error(NdbTransaction *trans,
@@ -836,8 +847,6 @@ private:
                                       const NdbOperation *last,
                                       uint errcode);
   int peek_indexed_rows(const byte *record);
-  int unique_index_read(const byte *key, uint key_len, 
-                        byte *buf);
   int fetch_next(NdbScanOperation* op);
   int next_result(byte *buf); 
   int define_read_attrs(byte* buf, NdbOperation* op);
@@ -903,6 +912,13 @@ private:
   int build_scan_filter(Ndb_cond* &cond, NdbScanFilter* filter);
   int generate_scan_filter(Ndb_cond_stack* cond_stack, 
                            NdbScanOperation* op);
+  int generate_scan_filter_from_cond(Ndb_cond_stack* cond_stack, 
+				     NdbScanFilter& filter);
+  int generate_scan_filter_from_key(NdbScanOperation* op,
+                                   const KEY* key_info, 
+                                   const byte *key, 
+                                   uint key_len,
+                                   byte *buf);
 
   friend int execute_commit(ha_ndbcluster*, NdbTransaction*);
   friend int execute_no_commit_ignore_no_key(ha_ndbcluster*, NdbTransaction*);