mariadb/sql/ha_ndbcluster.h

/* Copyright (C) 2000-2003 MySQL AB

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

/*
  This file defines the NDB Cluster handler: the interface between MySQL and
  NDB Cluster
*/

/* The class defining a handle to an NDB Cluster table */

#ifdef USE_PRAGMA_INTERFACE
#pragma interface                       /* gcc class implementation */
#endif

/* Blob tables and events are internal to NDB and must never be accessed */
#define IS_NDB_BLOB_PREFIX(A) is_prefix(A, "NDB$BLOB")

#include <NdbApi.hpp>
#include <ndbapi_limits.h>

#define NDB_HIDDEN_PRIMARY_KEY_LENGTH 8

class Ndb;             // Forward declaration
class NdbOperation;    // Forward declaration
class NdbTransaction;  // Forward declaration
class NdbRecAttr;      // Forward declaration
class NdbScanOperation; 
class NdbScanFilter; 
class NdbIndexScanOperation; 
class NdbBlob;
class NdbIndexStat;
class NdbEventOperation;

// connectstring to cluster if given by mysqld
extern const char *ndbcluster_connectstring;
extern ulong ndb_cache_check_time;
#ifdef HAVE_NDB_BINLOG
extern ulong ndb_report_thresh_binlog_epoch_slip;
extern ulong ndb_report_thresh_binlog_mem_usage;
#endif

typedef enum ndb_index_type {
  UNDEFINED_INDEX = 0,
  PRIMARY_KEY_INDEX = 1,
  PRIMARY_KEY_ORDERED_INDEX = 2,
  UNIQUE_INDEX = 3,
  UNIQUE_ORDERED_INDEX = 4,
  ORDERED_INDEX = 5
} NDB_INDEX_TYPE;

typedef enum ndb_index_status {
  UNDEFINED = 0,
  ACTIVE = 1,
  TO_BE_DROPPED = 2
} NDB_INDEX_STATUS;

typedef struct ndb_index_data {
  NDB_INDEX_TYPE type;
  NDB_INDEX_STATUS status;  
  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;
  // Simple counter mechanism to decide when to connect to db
  uint index_stat_update_freq;
  uint index_stat_query_count;
} NDB_INDEX_DATA;

typedef union { const NdbRecAttr *rec; NdbBlob *blob; void *ptr; } NdbValue;

int get_ndb_blobs_value(TABLE* table, NdbValue* value_array,
                        byte*& buffer, uint& buffer_size,
                        my_ptrdiff_t ptrdiff);

typedef enum {
  NSS_INITIAL= 0,
  NSS_DROPPED,
  NSS_ALTERED 
} NDB_SHARE_STATE;

typedef struct st_ndbcluster_share {
  NDB_SHARE_STATE state;
  MEM_ROOT mem_root;
  THR_LOCK lock;
  pthread_mutex_t mutex;
  char *key;
  uint key_length;
  THD *util_lock;
  uint use_count;
  uint commit_count_lock;
  ulonglong commit_count;
  char *db;
  char *table_name;
  Ndb::TupleIdRange tuple_id_range;
#ifdef HAVE_NDB_BINLOG
  uint32 connect_count;
  uint32 flags;
  NdbEventOperation *op;
  NdbEventOperation *op_old; // for rename table
  char *old_names; // for rename table
  TABLE_SHARE *table_share;
  TABLE *table;
  byte *record[2]; // pointer to allocated records for receiving data
  NdbValue *ndb_value[2];
  MY_BITMAP *subscriber_bitmap;
#endif
} NDB_SHARE;

inline
NDB_SHARE_STATE
get_ndb_share_state(NDB_SHARE *share)
{
  NDB_SHARE_STATE state;
  pthread_mutex_lock(&share->mutex);
  state= share->state;
  pthread_mutex_unlock(&share->mutex);
  return state;
}

inline
void
set_ndb_share_state(NDB_SHARE *share, NDB_SHARE_STATE state)
{
  pthread_mutex_lock(&share->mutex);
  share->state= state;
  pthread_mutex_unlock(&share->mutex);
}

struct Ndb_tuple_id_range_guard {
  Ndb_tuple_id_range_guard(NDB_SHARE* _share) :
    share(_share),
    range(share->tuple_id_range) {
    pthread_mutex_lock(&share->mutex);
  }
  ~Ndb_tuple_id_range_guard() {
    pthread_mutex_unlock(&share->mutex);
  }
  NDB_SHARE* share;
  Ndb::TupleIdRange& range;
};

#ifdef HAVE_NDB_BINLOG
/* NDB_SHARE.flags */
#define NSF_HIDDEN_PK 1 /* table has hidden primary key */
#define NSF_BLOB_FLAG 2 /* table has blob attributes */
#define NSF_NO_BINLOG 4 /* table should not be binlogged */
#endif

typedef enum ndb_item_type {
  NDB_VALUE = 0,   // Qualified more with Item::Type
  NDB_FIELD = 1,   // Qualified from table definition
  NDB_FUNCTION = 2,// Qualified from Item_func::Functype
  NDB_END_COND = 3 // End marker for condition group
} NDB_ITEM_TYPE;

typedef enum ndb_func_type {
  NDB_EQ_FUNC = 0,
  NDB_NE_FUNC = 1,
  NDB_LT_FUNC = 2,
  NDB_LE_FUNC = 3,
  NDB_GT_FUNC = 4,
  NDB_GE_FUNC = 5,
  NDB_ISNULL_FUNC = 6,
  NDB_ISNOTNULL_FUNC = 7,
  NDB_LIKE_FUNC = 8,
  NDB_NOTLIKE_FUNC = 9,
  NDB_NOT_FUNC = 10,
  NDB_UNKNOWN_FUNC = 11,
  NDB_COND_AND_FUNC = 12,
  NDB_COND_OR_FUNC = 13,
  NDB_UNSUPPORTED_FUNC = 14
} NDB_FUNC_TYPE;

typedef union ndb_item_qualification {
  Item::Type value_type; 
  enum_field_types field_type; // Instead of Item::FIELD_ITEM
  NDB_FUNC_TYPE function_type; // Instead of Item::FUNC_ITEM
} NDB_ITEM_QUALIFICATION;

typedef struct ndb_item_field_value {
  Field* field;
  int column_no;
} NDB_ITEM_FIELD_VALUE;

typedef union ndb_item_value {
  const Item *item;
  NDB_ITEM_FIELD_VALUE *field_value;
  uint arg_count;
} NDB_ITEM_VALUE;

struct negated_function_mapping
{
  NDB_FUNC_TYPE pos_fun;
  NDB_FUNC_TYPE neg_fun;
};


/*
  Define what functions can be negated in condition pushdown.
  Note, these HAVE to be in the same order as in definition enum
*/
static const negated_function_mapping neg_map[]= 
{
  {NDB_EQ_FUNC, NDB_NE_FUNC},
  {NDB_NE_FUNC, NDB_EQ_FUNC},
  {NDB_LT_FUNC, NDB_GE_FUNC},
  {NDB_LE_FUNC, NDB_GT_FUNC},
  {NDB_GT_FUNC, NDB_LE_FUNC},
  {NDB_GE_FUNC, NDB_LT_FUNC},
  {NDB_ISNULL_FUNC, NDB_ISNOTNULL_FUNC},
  {NDB_ISNOTNULL_FUNC, NDB_ISNULL_FUNC},
  {NDB_LIKE_FUNC, NDB_NOTLIKE_FUNC},
  {NDB_NOTLIKE_FUNC, NDB_LIKE_FUNC},
  {NDB_NOT_FUNC, NDB_UNSUPPORTED_FUNC},
  {NDB_UNKNOWN_FUNC, NDB_UNSUPPORTED_FUNC},
  {NDB_COND_AND_FUNC, NDB_UNSUPPORTED_FUNC},
  {NDB_COND_OR_FUNC, NDB_UNSUPPORTED_FUNC},
  {NDB_UNSUPPORTED_FUNC, NDB_UNSUPPORTED_FUNC}
};
  
/*
  This class is the construction element for serialization of Item tree 
  in condition pushdown.
  An instance of Ndb_Item represents a constant, table field reference,
  unary or binary comparison predicate, and start/end of AND/OR.
  Instances of Ndb_Item are stored in a linked list implemented by Ndb_cond
  class.
  The order of elements produced by Ndb_cond::next corresponds to
  breadth-first traversal of the Item (i.e. expression) tree in prefix order.
  AND and OR have arbitrary arity, so the end of AND/OR group is marked with  
  Ndb_item with type == NDB_END_COND.
  NOT items represent negated conditions and generate NAND/NOR groups.
*/
class Ndb_item {
 public:
  Ndb_item(NDB_ITEM_TYPE item_type) : type(item_type) {};
  Ndb_item(NDB_ITEM_TYPE item_type, 
           NDB_ITEM_QUALIFICATION item_qualification,
           const Item *item_value)
    : type(item_type), qualification(item_qualification)
  { 
    switch(item_type) {
    case(NDB_VALUE):
      value.item= item_value;
      break;
    case(NDB_FIELD): {
      NDB_ITEM_FIELD_VALUE *field_value= new NDB_ITEM_FIELD_VALUE();
      Item_field *field_item= (Item_field *) item_value;
      field_value->field= field_item->field;
      field_value->column_no= -1; // Will be fetched at scan filter generation
      value.field_value= field_value;
      break;
    }
    case(NDB_FUNCTION):
      value.item= item_value;
      value.arg_count= ((Item_func *) item_value)->argument_count();
      break;
    case(NDB_END_COND):
      break;
    }
  };
  Ndb_item(Field *field, int column_no) : type(NDB_FIELD)
  {
    NDB_ITEM_FIELD_VALUE *field_value= new NDB_ITEM_FIELD_VALUE();
    qualification.field_type= field->type();
    field_value->field= field;
    field_value->column_no= column_no;
    value.field_value= field_value;
  };
  Ndb_item(Item_func::Functype func_type, const Item *item_value) 
    : type(NDB_FUNCTION)
  {
    qualification.function_type= item_func_to_ndb_func(func_type);
    value.item= item_value;
    value.arg_count= ((Item_func *) item_value)->argument_count();
  };
  Ndb_item(Item_func::Functype func_type, uint no_args) 
    : type(NDB_FUNCTION)
  {
    qualification.function_type= item_func_to_ndb_func(func_type);
    value.arg_count= no_args;
  };
  ~Ndb_item()
  { 
    if (type == NDB_FIELD)
      {
        delete value.field_value;
        value.field_value= NULL;
      }
  };

  uint32 pack_length() 
  { 
    switch(type) {
    case(NDB_VALUE):
      if(qualification.value_type == Item::STRING_ITEM)
        return value.item->str_value.length();
      break;
    case(NDB_FIELD):
      return value.field_value->field->pack_length(); 
    default:
      break;
    }
    
    return 0;
  };

  Field * get_field() { return value.field_value->field; };

  int get_field_no() { return value.field_value->column_no; };

  int argument_count() 
  { 
    return value.arg_count;
  };

  const char* get_val() 
  {  
    switch(type) {
    case(NDB_VALUE):
      if(qualification.value_type == Item::STRING_ITEM)
        return value.item->str_value.ptr();
      break;
    case(NDB_FIELD):
      return value.field_value->field->ptr; 
    default:
      break;
    }
    
    return NULL;
  };

  void save_in_field(Ndb_item *field_item)
  {
    Field *field = field_item->value.field_value->field;
    const Item *item= value.item;

    if (item && field)
    {
      my_bitmap_map *old_map=
        dbug_tmp_use_all_columns(field->table, field->table->write_set);
      ((Item *)item)->save_in_field(field, FALSE);
      dbug_tmp_restore_column_map(field->table->write_set, old_map);
    }
  };

  static NDB_FUNC_TYPE item_func_to_ndb_func(Item_func::Functype fun)
  {
    switch (fun) {
    case (Item_func::EQ_FUNC): { return NDB_EQ_FUNC; }
    case (Item_func::NE_FUNC): { return NDB_NE_FUNC; }
    case (Item_func::LT_FUNC): { return NDB_LT_FUNC; }
    case (Item_func::LE_FUNC): { return NDB_LE_FUNC; }
    case (Item_func::GT_FUNC): { return NDB_GT_FUNC; }
    case (Item_func::GE_FUNC): { return NDB_GE_FUNC; }
    case (Item_func::ISNULL_FUNC): { return NDB_ISNULL_FUNC; }
    case (Item_func::ISNOTNULL_FUNC): { return NDB_ISNOTNULL_FUNC; }
    case (Item_func::LIKE_FUNC): { return NDB_LIKE_FUNC; }
    case (Item_func::NOT_FUNC): { return NDB_NOT_FUNC; }
    case (Item_func::UNKNOWN_FUNC): { return NDB_UNKNOWN_FUNC; }
    case (Item_func::COND_AND_FUNC): { return NDB_COND_AND_FUNC; }
    case (Item_func::COND_OR_FUNC): { return NDB_COND_OR_FUNC; }
    default: { return NDB_UNSUPPORTED_FUNC; }
    }
  };

  static NDB_FUNC_TYPE negate(NDB_FUNC_TYPE fun)
  {
    uint i= (uint) fun;
    DBUG_ASSERT(fun == neg_map[i].pos_fun);
    return  neg_map[i].neg_fun;
  };

  NDB_ITEM_TYPE type;
  NDB_ITEM_QUALIFICATION qualification;
 private:
  NDB_ITEM_VALUE value;
};

/*
  This class implements a linked list used for storing a
  serialization of the Item tree for condition pushdown.
 */
class Ndb_cond 
{
 public:
  Ndb_cond() : ndb_item(NULL), next(NULL), prev(NULL) {};
  ~Ndb_cond() 
  { 
    if (ndb_item) delete ndb_item; 
    ndb_item= NULL; 
    if (next) delete next;
    next= prev= NULL; 
  };
  Ndb_item *ndb_item;
  Ndb_cond *next;
  Ndb_cond *prev;
};

/*
  This class implements a stack for storing several conditions
  for pushdown (represented as serialized Item trees using Ndb_cond).
  The current implementation only pushes one condition, but is
  prepared for handling several (C1 AND C2 ...) if the logic for 
  pushing conditions is extended in sql_select.
*/
class Ndb_cond_stack 
{
 public:
  Ndb_cond_stack() : ndb_cond(NULL), next(NULL) {};
  ~Ndb_cond_stack() 
  { 
    if (ndb_cond) delete ndb_cond; 
    ndb_cond= NULL; 
    if (next) delete next;
    next= NULL; 
  };
  Ndb_cond *ndb_cond;
  Ndb_cond_stack *next;
};

class Ndb_rewrite_context
{
public:
  Ndb_rewrite_context(Item_func *func) 
    : func_item(func), left_hand_item(NULL), count(0) {};
  ~Ndb_rewrite_context()
  {
    if (next) delete next;
  }
  const Item_func *func_item;
  const Item *left_hand_item;
  uint count;
  Ndb_rewrite_context *next;
};

/*
  This class is used for storing the context when traversing
  the Item tree. It stores a reference to the table the condition
  is defined on, the serialized representation being generated, 
  if the condition found is supported, and information what is
  expected next in the tree inorder for the condition to be supported.
*/
class Ndb_cond_traverse_context 
{
 public:
  Ndb_cond_traverse_context(TABLE *tab, void* ndb_tab, Ndb_cond_stack* stack)
    : table(tab), ndb_table(ndb_tab), 
    supported(TRUE), stack_ptr(stack), cond_ptr(NULL),
    skip(0), collation(NULL), rewrite_stack(NULL)
  {
    // Allocate type checking bitmaps   
    bitmap_init(&expect_mask, 0, 512, FALSE);
    bitmap_init(&expect_field_type_mask, 0, 512, FALSE);
    bitmap_init(&expect_field_result_mask, 0, 512, FALSE);

    if (stack)
      cond_ptr= stack->ndb_cond;
  };
  ~Ndb_cond_traverse_context()
  {
    bitmap_free(&expect_mask);
    bitmap_free(&expect_field_type_mask);
    bitmap_free(&expect_field_result_mask);
    if (rewrite_stack) delete rewrite_stack;
  }
  void expect(Item::Type type)
  {
    bitmap_set_bit(&expect_mask, (uint) type);
    if (type == Item::FIELD_ITEM) expect_all_field_types();
  };
  void dont_expect(Item::Type type)
  {
    bitmap_clear_bit(&expect_mask, (uint) type);
  };
  bool expecting(Item::Type type)
  {
    return bitmap_is_set(&expect_mask, (uint) type);
  };
  void expect_nothing()
  {
    bitmap_clear_all(&expect_mask);
  };
  bool expecting_nothing()
  {
    return bitmap_is_clear_all(&expect_mask);
  }
  void expect_only(Item::Type type)
  {
    expect_nothing();
    expect(type);
  };

  void expect_field_type(enum_field_types type)
  {
    bitmap_set_bit(&expect_field_type_mask, (uint) type);
  };
  void expect_all_field_types()
  {
    bitmap_set_all(&expect_field_type_mask);
  };
  bool expecting_field_type(enum_field_types type)
  {
    return bitmap_is_set(&expect_field_type_mask, (uint) type);
  };
  void expect_no_field_type()
  {
    bitmap_clear_all(&expect_field_type_mask);
  };
  bool expecting_no_field_type()
  {
    return bitmap_is_clear_all(&expect_field_type_mask);
  }
  void expect_only_field_type(enum_field_types result)
  {
    expect_no_field_type();
    expect_field_type(result);
  };

  void expect_field_result(Item_result result)
  {
    bitmap_set_bit(&expect_field_result_mask, (uint) result);
  };
  bool expecting_field_result(Item_result result)
  {
    return bitmap_is_set(&expect_field_result_mask, (uint) result);
  };
  void expect_no_field_result()
  {
    bitmap_clear_all(&expect_field_result_mask);
  };
  bool expecting_no_field_result()
  {
    return bitmap_is_clear_all(&expect_field_result_mask);
  }
  void expect_only_field_result(Item_result result)
  {
    expect_no_field_result();
    expect_field_result(result);
  };
  void expect_collation(CHARSET_INFO* col)
  {
    collation= col;
  };
  bool expecting_collation(CHARSET_INFO* col)
  {
    bool matching= (!collation) ? true : (collation == col);
    collation= NULL;

    return matching;
  };

  TABLE* table;
  void* ndb_table;
  bool supported;
  Ndb_cond_stack* stack_ptr;
  Ndb_cond* cond_ptr;
  MY_BITMAP expect_mask;
  MY_BITMAP expect_field_type_mask;
  MY_BITMAP expect_field_result_mask;
  uint skip;
  CHARSET_INFO* collation;
  Ndb_rewrite_context *rewrite_stack;
};


typedef enum ndb_query_state_bits {
  NDB_QUERY_NORMAL = 0,
  NDB_QUERY_MULTI_READ_RANGE = 1
} NDB_QUERY_STATE_BITS;

/*
  Place holder for ha_ndbcluster thread specific data
*/

enum THD_NDB_OPTIONS
{
  TNO_NO_LOG_SCHEMA_OP= 1 << 0
};

struct Ndb_local_table_statistics {
  int no_uncommitted_rows_count;
  ulong last_count;
  ha_rows records;
};

typedef struct st_thd_ndb_share {
  const void *key;
  struct Ndb_local_table_statistics stat;
} THD_NDB_SHARE;

class Thd_ndb 
{
 public:
  Thd_ndb();
  ~Thd_ndb();

  void init_open_tables();
  THD_NDB_SHARE *get_open_table(THD *thd, const void *key);

  Ndb *ndb;
  ulong count;
  uint lock_count;
  NdbTransaction *all;
  NdbTransaction *stmt;
  int error;
  uint32 options;
  List<NDB_SHARE> changed_tables;
  uint query_state;
  HASH open_tables;
};

class ha_ndbcluster: public handler
{
 public:
  ha_ndbcluster(handlerton *hton, TABLE_SHARE *table);
  ~ha_ndbcluster();

  int ha_initialise();
  int open(const char *name, int mode, uint test_if_locked);
  int close(void);

  int write_row(byte *buf);
  int update_row(const byte *old_data, byte *new_data);
  int delete_row(const byte *buf);
  int index_init(uint index, bool sorted);
  int index_end();
  int index_read(byte *buf, const byte *key, uint key_len, 
                 enum ha_rkey_function find_flag);
  int index_next(byte *buf);
  int index_prev(byte *buf);
  int index_first(byte *buf);
  int index_last(byte *buf);
  int index_read_last(byte * buf, const byte * key, uint key_len);
  int rnd_init(bool scan);
  int rnd_end();
  int rnd_next(byte *buf);
  int rnd_pos(byte *buf, byte *pos);
  void position(const byte *record);
  int read_range_first(const key_range *start_key,
                       const key_range *end_key,
                       bool eq_range, bool sorted);
  int read_range_first_to_buf(const key_range *start_key,
                              const key_range *end_key,
                              bool eq_range, bool sorted,
                              byte* buf);
  int read_range_next();
  int alter_tablespace(st_alter_tablespace *info);

  /**
   * Multi range stuff
   */
  int read_multi_range_first(KEY_MULTI_RANGE **found_range_p,
                             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();
  ha_rows estimate_rows_upper_bound()
    { return HA_POS_ERROR; }
  int info(uint);
  void get_dynamic_partition_info(PARTITION_INFO *stat_info, uint part_id);
  int extra(enum ha_extra_function operation);
  int extra_opt(enum ha_extra_function operation, ulong cache_size);
  int reset();
  int external_lock(THD *thd, int lock_type);
  void unlock_row();
  int start_stmt(THD *thd, thr_lock_type lock_type);
  void print_error(int error, myf errflag);
  const char * table_type() const;
  const char ** bas_ext() const;
  ulonglong table_flags(void) const;
  void prepare_for_alter();
  int add_index(TABLE *table_arg, KEY *key_info, uint num_of_keys);
  int prepare_drop_index(TABLE *table_arg, uint *key_num, uint num_of_keys);
  int final_drop_index(TABLE *table_arg);
  void set_part_info(partition_info *part_info);
  ulong index_flags(uint idx, uint part, bool all_parts) const;
  uint max_supported_record_length() const;
  uint max_supported_keys() const;
  uint max_supported_key_parts() const;
  uint max_supported_key_length() const;
  uint max_supported_key_part_length() const;

  int rename_table(const char *from, const char *to);
  int delete_table(const char *name);
  int create(const char *name, TABLE *form, HA_CREATE_INFO *info);
  int create_handler_files(const char *file, const char *old_name,
                           int action_flag, HA_CREATE_INFO *info);
  int get_default_no_partitions(HA_CREATE_INFO *info);
  bool get_no_parts(const char *name, uint *no_parts);
  void set_auto_partitions(partition_info *part_info);
  virtual bool is_fatal_error(int error, uint flags)
  {
    if (!handler::is_fatal_error(error, flags) ||
        error == HA_ERR_NO_PARTITION_FOUND)
      return FALSE;
    return TRUE;
  }

  THR_LOCK_DATA **store_lock(THD *thd,
                             THR_LOCK_DATA **to,
                             enum thr_lock_type lock_type);

  bool low_byte_first() const;

  const char* index_type(uint key_number);

  double scan_time();
  ha_rows records_in_range(uint inx, key_range *min_key, key_range *max_key);
  void start_bulk_insert(ha_rows rows);
  int end_bulk_insert();

  static Thd_ndb* seize_thd_ndb();
  static void release_thd_ndb(Thd_ndb* thd_ndb);
 
static void set_dbname(const char *pathname, char *dbname);
static void set_tabname(const char *pathname, char *tabname);

  /*
    Condition pushdown
  */

 /*
   Push condition down to the table handler.
   SYNOPSIS
     cond_push()
     cond   Condition to be pushed. The condition tree must not be
     modified by the by the caller.
   RETURN
     The 'remainder' condition that caller must use to filter out records.
     NULL means the handler will not return rows that do not match the
     passed condition.
   NOTES
   The pushed conditions form a stack (from which one can remove the
   last pushed condition using cond_pop).
   The table handler filters out rows using (pushed_cond1 AND pushed_cond2 
   AND ... AND pushed_condN)
   or less restrictive condition, depending on handler's capabilities.
   
   handler->reset() call empties the condition stack.
   Calls to rnd_init/rnd_end, index_init/index_end etc do not affect the  
   condition stack.
   The current implementation supports arbitrary AND/OR nested conditions
   with comparisons between columns and constants (including constant
   expressions and function calls) and the following comparison operators:
   =, !=, >, >=, <, <=, like, "not like", "is null", and "is not null". 
   Negated conditions are supported by NOT which generate NAND/NOR groups.
 */ 
  const COND *cond_push(const COND *cond);
 /*
   Pop the top condition from the condition stack of the handler instance.
   SYNOPSIS
     cond_pop()
     Pops the top if condition stack, if stack is not empty
 */
  void cond_pop();

  uint8 table_cache_type();

  /*
   * Internal to ha_ndbcluster, used by C functions
   */
  int ndb_err(NdbTransaction*);

  my_bool register_query_cache_table(THD *thd, char *table_key,
                                     uint key_length,
                                     qc_engine_callback *engine_callback,
                                     ulonglong *engine_data);

  bool check_if_incompatible_data(HA_CREATE_INFO *info,
				  uint table_changes);

private:
  friend int ndbcluster_drop_database_impl(const char *path);
  friend int ndb_handle_schema_change(THD *thd, 
                                      Ndb *ndb, NdbEventOperation *pOp,
                                      NDB_SHARE *share);

  static int delete_table(ha_ndbcluster *h, Ndb *ndb,
			  const char *path,
			  const char *db,
			  const char *table_name);
  int create_ndb_index(const char *name, KEY *key_info, bool unique);
  int create_ordered_index(const char *name, KEY *key_info);
  int create_unique_index(const char *name, KEY *key_info);
  int create_index(const char *name, KEY *key_info, 
                   NDB_INDEX_TYPE idx_type, uint idx_no);
// Index list management
  int create_indexes(Ndb *ndb, TABLE *tab);
  int open_indexes(Ndb *ndb, TABLE *tab, bool ignore_error);
  void renumber_indexes(Ndb *ndb, TABLE *tab);
  int drop_indexes(Ndb *ndb, TABLE *tab);
  int add_index_handle(THD *thd, NdbDictionary::Dictionary *dict,
                       KEY *key_info, const char *index_name, uint index_no);
  int get_metadata(const char* path);
  void release_metadata(THD *thd, Ndb *ndb);
  NDB_INDEX_TYPE get_index_type(uint idx_no) const;
  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;
  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,
                             void *tab);
  char* get_tablespace_name(THD *thd, char *name, uint name_len);
  int set_range_data(void *tab, partition_info* part_info);
  int set_list_data(void *tab, partition_info* part_info);
  int complemented_read(const byte *old_data, byte *new_data,
                        uint32 old_part_id);
  int pk_read(const byte *key, uint key_len, byte *buf, uint32 part_id);
  int ordered_index_scan(const key_range *start_key,
                         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,
                                      const NdbOperation *first,
                                      const NdbOperation *last,
                                      uint errcode);
  int peek_indexed_rows(const byte *record, bool check_pk);
  int fetch_next(NdbScanOperation* op);
  int next_result(byte *buf); 
  int define_read_attrs(byte* buf, NdbOperation* op);
  int filtered_scan(const byte *key, uint key_len, 
                    byte *buf,
                    enum ha_rkey_function find_flag);
  int close_scan();
  void unpack_record(byte *buf);
  int get_ndb_lock_type(enum thr_lock_type type);

  void set_dbname(const char *pathname);
  void set_tabname(const char *pathname);

  bool set_hidden_key(NdbOperation*,
                      uint fieldnr, const byte* field_ptr);
  int set_ndb_key(NdbOperation*, Field *field,
                  uint fieldnr, const byte* field_ptr);
  int set_ndb_value(NdbOperation*, Field *field, uint fieldnr,
		    int row_offset= 0, bool *set_blob_value= 0);
  int get_ndb_value(NdbOperation*, Field *field, uint fieldnr, byte*);
  int get_ndb_partition_id(NdbOperation *);
  friend int g_get_ndb_blobs_value(NdbBlob *ndb_blob, void *arg);
  int set_primary_key(NdbOperation *op, const byte *key);
  int set_primary_key_from_record(NdbOperation *op, const byte *record);
  int set_index_key_from_record(NdbOperation *op, const byte *record,
                                uint keyno);
  int set_bounds(NdbIndexScanOperation*, uint inx, bool rir,
                 const key_range *keys[2], uint= 0);
  int key_cmp(uint keynr, const byte * old_row, const byte * new_row);
  int set_index_key(NdbOperation *, const KEY *key_info, const byte *key_ptr);
  void print_results();

  virtual void get_auto_increment(ulonglong offset, ulonglong increment,
                                  ulonglong nb_desired_values,
                                  ulonglong *first_value,
                                  ulonglong *nb_reserved_values);
  bool uses_blob_value();

  char *update_table_comment(const char * comment);

  int write_ndb_file(const char *name);

  int check_ndb_connection(THD* thd= current_thd);

  void set_rec_per_key();
  int records_update();
  void no_uncommitted_rows_execute_failure();
  void no_uncommitted_rows_update(int);
  void no_uncommitted_rows_reset(THD *);

  void release_completed_operations(NdbTransaction*, bool);

  /*
    Condition pushdown
  */
  void cond_clear();
  bool serialize_cond(const COND *cond, Ndb_cond_stack *ndb_cond);
  int build_scan_filter_predicate(Ndb_cond* &cond, 
                                  NdbScanFilter* filter,
                                  bool negated= false);
  int build_scan_filter_group(Ndb_cond* &cond, 
                              NdbScanFilter* filter);
  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*);
  friend int execute_no_commit(ha_ndbcluster*, NdbTransaction*, bool);
  friend int execute_no_commit_ie(ha_ndbcluster*, NdbTransaction*, bool);

  NdbTransaction *m_active_trans;
  NdbScanOperation *m_active_cursor;
  const NdbDictionary::Table *m_table;
  struct Ndb_local_table_statistics *m_table_info;
  char m_dbname[FN_HEADLEN];
  //char m_schemaname[FN_HEADLEN];
  char m_tabname[FN_HEADLEN];
  ulonglong m_table_flags;
  THR_LOCK_DATA m_lock;
  bool m_lock_tuple;
  NDB_SHARE *m_share;
  NDB_INDEX_DATA  m_index[MAX_KEY];
  THD_NDB_SHARE *m_thd_ndb_share;
  // NdbRecAttr has no reference to blob
  NdbValue m_value[NDB_MAX_ATTRIBUTES_IN_TABLE];
  byte m_ref[NDB_HIDDEN_PRIMARY_KEY_LENGTH];
  partition_info *m_part_info;
  uint32 m_part_id;
  byte *m_rec0;
  Field **m_part_field_array;
  bool m_use_partition_function;
  bool m_sorted;
  bool m_use_write;
  bool m_ignore_dup_key;
  bool m_has_unique_index;
  bool m_primary_key_update;
  bool m_write_op;
  bool m_ignore_no_key;
  ha_rows m_rows_to_insert; // TODO: merge it with handler::estimation_rows_to_insert?
  ha_rows m_rows_inserted;
  ha_rows m_bulk_insert_rows;
  ha_rows m_rows_changed;
  bool m_bulk_insert_not_flushed;
  ha_rows m_ops_pending;
  bool m_skip_auto_increment;
  bool m_blobs_pending;
  my_ptrdiff_t m_blobs_offset;
  // memory for blobs in one tuple
  char *m_blobs_buffer;
  uint32 m_blobs_buffer_size;
  uint m_dupkey;
  // set from thread variables at external lock
  bool m_ha_not_exact_count;
  bool m_force_send;
  ha_rows m_autoincrement_prefetch;
  bool m_transaction_on;

  Ndb_cond_stack *m_cond_stack;
  bool m_disable_multi_read;
  byte *m_multi_range_result_ptr;
  KEY_MULTI_RANGE *m_multi_ranges;
  KEY_MULTI_RANGE *m_multi_range_defined;
  const NdbOperation *m_current_multi_operation;
  NdbIndexScanOperation *m_multi_cursor;
  byte *m_multi_range_cursor_result_ptr;
  int setup_recattr(const NdbRecAttr*);
  Ndb *get_ndb();
};

extern SHOW_VAR ndb_status_variables[];

int ndbcluster_discover(THD* thd, const char* dbname, const char* name,
                        const void** frmblob, uint* frmlen);
int ndbcluster_find_files(THD *thd,const char *db,const char *path,
                          const char *wild, bool dir, List<char> *files);
int ndbcluster_table_exists_in_engine(THD* thd,
                                      const char *db, const char *name);
void ndbcluster_print_error(int error, const NdbOperation *error_op);

static const char ndbcluster_hton_name[]= "ndbcluster";
static const int ndbcluster_hton_name_length=sizeof(ndbcluster_hton_name)-1;