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; either version 2 of the License, or
   (at your option) any later version.

   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 __GNUC__
#pragma interface                       /* gcc class implementation */
#endif

#include <ndbapi_limits.h>

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

// connectstring to cluster if given by mysqld
extern const char *ndbcluster_connectstring;
extern ulong ndb_cache_check_time;

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 struct ndb_index_data {
  NDB_INDEX_TYPE type;
  void *index;
  void *unique_index;
  unsigned char *unique_index_attrid_map;
} NDB_INDEX_DATA;

typedef struct st_ndbcluster_share {
  THR_LOCK lock;
  pthread_mutex_t mutex;
  char *table_name;
  uint table_name_length,use_count;
  uint commit_count_lock;
  ulonglong commit_count;
} NDB_SHARE;

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 union ndb_item_qualification {
  Item::Type value_type; 
  enum_field_types field_type;       // Instead of Item::FIELD_ITEM
  Item_func::Functype 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;
} NDB_ITEM_VALUE;

struct negated_function_mapping
{
  Item_func::Functype pos_fun;
  Item_func::Functype neg_fun;
};

static const negated_function_mapping neg_map[]= 
{
  {Item_func::EQ_FUNC, Item_func::NE_FUNC},
  {Item_func::NE_FUNC, Item_func::EQ_FUNC},
  {Item_func::LT_FUNC, Item_func::GE_FUNC},
  {Item_func::LE_FUNC, Item_func::GT_FUNC},
  {Item_func::GT_FUNC, Item_func::LE_FUNC},
  {Item_func::GE_FUNC, Item_func::LT_FUNC},
  {Item_func::LIKE_FUNC, Item_func::NOTLIKE_FUNC},
  {Item_func::NOTLIKE_FUNC, Item_func::LIKE_FUNC},
  {Item_func::ISNULL_FUNC, Item_func::ISNOTNULL_FUNC},
  {Item_func::ISNOTNULL_FUNC, Item_func::ISNULL_FUNC},
  {Item_func::UNKNOWN_FUNC, Item_func::NOT_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;
      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= func_type;
    value.item= item_value;
  };
  ~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 ((Item_func *) value.item)->argument_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)
      ((Item *)item)->save_in_field(field, false);
  };

  static Item_func::Functype negate(Item_func::Functype fun)
  {
    uint i;
    for (i=0; 
         fun != neg_map[i].pos_fun &&
           neg_map[i].pos_fun != Item_func::UNKNOWN_FUNC;
         i++);
    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; 
    next= NULL; 
  };
  Ndb_cond *ndb_cond;
  Ndb_cond_stack *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),
    expect_mask(0), expect_field_result_mask(0), skip(0), collation(NULL)
  {
    if (stack)
      cond_ptr= stack->ndb_cond;
  };
  void expect(Item::Type type)
  {
    expect_mask|= (1 << type);
  };
  void dont_expect(Item::Type type)
  {
    expect_mask&= ~(1 << type);
  };
  bool expecting(Item::Type type)
  {
    return (expect_mask & (1 << type));
  };
  void expect_nothing()
  {
    expect_mask= 0;
  };
  void expect_only(Item::Type type)
  {
    expect_mask= 0;
    expect(type);
  };

  void expect_field_result(Item_result result)
  {
    expect_field_result_mask|= (1 << result);
  };
  bool expecting_field_result(Item_result result)
  {
    return (expect_field_result_mask & (1 << result));
  };
  void expect_no_field_result()
  {
    expect_field_result_mask= 0;
  };
  void expect_only_field_result(Item_result result)
  {
    expect_field_result_mask= 0;
    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;
  uint expect_mask;
  uint expect_field_result_mask;
  uint skip;
  CHARSET_INFO* collation;

};

/*
  Place holder for ha_ndbcluster thread specific data
*/

class Thd_ndb 
{
 public:
  Thd_ndb();
  ~Thd_ndb();
  Ndb *ndb;
  ulong count;
  uint lock_count;
  NdbTransaction *all;
  NdbTransaction *stmt;
  int error;
  List<NDB_SHARE> changed_tables;
};

class ha_ndbcluster: public handler
{
 public:
  ha_ndbcluster(TABLE *table);
  ~ha_ndbcluster();

  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);
  int index_end();
  int index_read(byte *buf, const byte *key, uint key_len, 
                 enum ha_rkey_function find_flag);
  int index_read_idx(byte *buf, uint index, 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();

  /**
   * 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 get_error_message(int error, String *buf);
  void info(uint);
  int extra(enum ha_extra_function operation);
  int extra_opt(enum ha_extra_function operation, ulong cache_size);
  int external_lock(THD *thd, int lock_type);
  int start_stmt(THD *thd);
  const char * table_type() const;
  const char ** bas_ext() const;
  ulong table_flags(void) const;
  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;

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

  bool low_byte_first() const;
  bool has_transactions();
  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);
 
  /*
    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->extra(HA_EXTRA_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();
  my_bool register_query_cache_table(THD *thd, char *table_key,
                                     uint key_length,
                                     qc_engine_callback *engine_callback,
                                     ulonglong *engine_data);
private:
  int alter_table_name(const char *to);
  int drop_table();
  int create_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 initialize_autoincrement(const void *table);
  enum ILBP {ILBP_CREATE = 0, ILBP_OPEN = 1}; // Index List Build Phase
  int build_index_list(TABLE *tab, enum ILBP phase);
  int get_metadata(const char* path);
  void release_metadata();
  NDB_INDEX_TYPE get_index_type(uint idx_no) const;
  NDB_INDEX_TYPE get_index_type_from_table(uint index_no) const;
  int check_index_fields_not_null(uint index_no);

  int pk_read(const byte *key, uint key_len, byte *buf);
  int complemented_pk_read(const byte *old_data, byte *new_data);
  int peek_row();
  int unique_index_read(const byte *key, uint key_len, 
                        byte *buf);
  int ordered_index_scan(const key_range *start_key,
                         const key_range *end_key,
                         bool sorted, bool descending, byte* buf);
  int full_table_scan(byte * buf);
  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);
  void set_tabname(const char *pathname, char *tabname);

  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, bool *set_blob_value= 0);
  int get_ndb_value(NdbOperation*, Field *field, uint fieldnr, byte*);
  friend int g_get_ndb_blobs_value(NdbBlob *ndb_blob, void *arg);
  int get_ndb_blobs_value(NdbBlob *last_ndb_blob);
  int set_primary_key(NdbOperation *op, const byte *key);
  int set_primary_key(NdbOperation *op);
  int set_primary_key_from_old_data(NdbOperation *op, const byte *old_data);
  int set_bounds(NdbIndexScanOperation*, 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();

  ulonglong get_auto_increment();
  void invalidateDictionaryCache();
  int ndb_err(NdbTransaction*);
  bool uses_blob_value(bool all_fields);

  char *update_table_comment(const char * comment);

  int write_ndb_file();

  int check_ndb_connection(THD* thd= current_thd);

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

  /*
    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);

  friend int execute_commit(ha_ndbcluster*, NdbTransaction*);
  friend int execute_no_commit(ha_ndbcluster*, NdbTransaction*);
  friend int execute_no_commit_ie(ha_ndbcluster*, NdbTransaction*);

  NdbTransaction *m_active_trans;
  NdbScanOperation *m_active_cursor;
  void *m_table;
  void *m_table_info;
  char m_dbname[FN_HEADLEN];
  //char m_schemaname[FN_HEADLEN];
  char m_tabname[FN_HEADLEN];
  ulong m_table_flags;
  THR_LOCK_DATA m_lock;
  NDB_SHARE *m_share;
  NDB_INDEX_DATA  m_index[MAX_KEY];
  // NdbRecAttr has no reference to blob
  typedef union { const NdbRecAttr *rec; NdbBlob *blob; void *ptr; } NdbValue;
  NdbValue m_value[NDB_MAX_ATTRIBUTES_IN_TABLE];
  bool m_use_write;
  bool m_ignore_dup_key;
  bool m_primary_key_update;
  bool m_retrieve_all_fields;
  bool m_retrieve_primary_key;
  ha_rows m_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;
  // 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 struct show_var_st ndb_status_variables[];

handlerton *ndbcluster_init(void);
bool ndbcluster_end(void);

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(THD* thd, const char *db, const char *name);
int ndbcluster_drop_database(const char* path);

void ndbcluster_print_error(int error, const NdbOperation *error_op);