Issue percona#17: Automatic per-index column families

Add support for INDEX idx(col1, ...) COMMENT '$per_index_cf'

storage/rocksdb/ha_rocksdb.cc

@@ -1207,13 +1207,16 @@ int ha_rocksdb::open(const char *name, int mode, uint test_if_locked)
 
   uint key_len= table->key_info[table->s->primary_key].key_length;
 
-  const char *comment= table->key_info[table->s->primary_key].comment.str;
+  const char *comment=  table->key_info[table->s->primary_key].comment.str;
+  const char *idx_name= table->key_info[table->s->primary_key].name;
   rocksdb::ColumnFamilyHandle *cf_handle;
-  if (!(cf_handle= cf_manager.get_cf(comment)))
+  bool is_auto_cf;
+  if (!(cf_handle= cf_manager.get_cf(comment, fullname.c_ptr(), idx_name,
+                                     &is_auto_cf)))
     DBUG_RETURN(HA_ERR_INTERNAL_ERROR);
 
   pk_descr->setup(table);  // move this into get_share() ??
-  pk_descr->set_cf_handle(cf_handle);
+  pk_descr->set_cf_handle(cf_handle, is_auto_cf);
 
   uint packed_key_len= pk_descr->max_storage_fmt_length();
 
@@ -1229,11 +1232,13 @@ int ha_rocksdb::open(const char *name, int mode, uint test_if_locked)
       continue;
 
     comment= table->key_info[i].comment.str;
-    if (!(cf_handle= cf_manager.get_cf(comment)))
+    idx_name= table->key_info[i].name;
+    if (!(cf_handle= cf_manager.get_cf(comment, fullname.c_ptr(), idx_name,
+                                       &is_auto_cf)))
       DBUG_RETURN(HA_ERR_INTERNAL_ERROR);
 
     key_descr[i]->setup(table);  // move this into get_share() ??
-    key_descr[i]->set_cf_handle(cf_handle);
+    key_descr[i]->set_cf_handle(cf_handle, is_auto_cf);
 
     uint packed_len= key_descr[i]->max_storage_fmt_length();
     if (packed_len > max_packed_sec_key_len)
@@ -1352,12 +1357,21 @@ int ha_rocksdb::create_key_defs(TABLE *table_arg, const char *db_table, uint len
       NULL, and it means use the default column family.
     */
     const char *comment= table_arg->key_info[i].comment.str;
-    cf_handle= cf_manager.get_or_create_cf(rdb, comment);
+    if (looks_like_per_index_cf_typo(comment))
+    {
+      my_error(ER_NOT_SUPPORTED_YET, MYF(0),
+               "column family name looks like a typo of $per_index_cf");
+      goto error;
+    }
+    bool is_auto_cf;
+    cf_handle= cf_manager.get_or_create_cf(rdb, comment, db_table,
+                                           table_arg->key_info[i].name,
+                                           &is_auto_cf);
     if (!cf_handle)
       goto error;
 
     if (!(key_descr[i]= new RDBSE_KEYDEF(ddl_manager.get_next_number(), i,
-                                         cf_handle)))
+                                         cf_handle, is_auto_cf)))
       goto error;
   }
   pk_descr= key_descr[table_arg->s->primary_key];
@@ -2802,6 +2816,32 @@ int ha_rocksdb::rename_table(const char *from, const char *to)
   if (rocksdb_normalize_tablename(to, &to_str))
     return HA_ERR_INTERNAL_ERROR;
 
+  /* Check if any index has a per-index column family */
+  {
+    /*
+      We can't check this directly, because
+      1. the object that referred to the old table has been close()d.
+      2. this ha_rocksdb object has no connection to any table at all, it has
+         been just created with (TABLE*)NULL.
+
+      So, we have to find the old table in the ddl_manager (it's there because
+      it has been opened by this statement), and check is_auto_cf there.
+    */
+    RDBSE_TABLE_DEF *tdef;
+    if (!(tdef= ddl_manager.find((uchar*)from_str.c_ptr(), from_str.length())))
+      return HA_ERR_INTERNAL_ERROR;
+
+    for (uint i= 0; i < tdef->n_keys; i++)
+    {
+      if (tdef->key_descr[i]->is_auto_cf)
+      {
+        my_error(ER_NOT_SUPPORTED_YET, MYF(0),
+                 "ALTER TABLE on table with per-index CF");
+        return HA_ERR_INTERNAL_ERROR;
+      }
+    }
+  }
+
   if (ddl_manager.rename((uchar*)from_str.ptr(), from_str.length(),
                          (uchar*)to_str.ptr(), to_str.length(), rdb))
     return HA_ERR_INTERNAL_ERROR;

storage/rocksdb/ha_rocksdb.h

@@ -33,8 +33,27 @@
 
 #include "rdb_applyiter.h"
 
+
+/*
+  This is
+  - the name of the default Column Family (the CF which stores indexes which didn't
+    explicity specify which CF they are in)
+  - the name used to set the default column family parameter for per-cf
+    arguments.
+*/
 const char * const DEFAULT_CF_NAME= "default";
 
+/*
+  Column family name which means "put this index into its own column family".
+  See get_per_index_cf_name.
+*/
+const char * const PER_INDEX_CF_NAME = "$per_index_cf";
+
+inline bool looks_like_per_index_cf_typo(const char *name)
+{
+  return (name && name[0]=='$' && strcmp(name, PER_INDEX_CF_NAME));
+}
+
 //#ifdef HAVE_PSI_INTERFACE
 extern PSI_stage_info stage_waiting_on_row_lock;
 

storage/rocksdb/rdb_cf_manager.cc

@@ -49,55 +49,119 @@ void Column_family_manager::cleanup()
 }
 
 
+/*
+  Generate Column Family name for per-index column families
+
+  @param res  OUT  Column Family name
+*/
+
+void get_per_index_cf_name(const char *db_table_name, const char *index_name,
+                           std::string *res)
+{
+  res->assign(db_table_name);
+  res->append(".");
+  res->append(index_name);
+}
+
+
+/*
+  @brief
+  Find column family by name. If it doesn't exist, create it
+
+  @detail
+    See Column_family_manager::get_cf
+*/
 rocksdb::ColumnFamilyHandle*
-Column_family_manager::get_or_create_cf(rocksdb::DB *rdb, const char *name)
+Column_family_manager::get_or_create_cf(rocksdb::DB *rdb, const char *cf_name,
+                                        const char *db_table_name,
+                                        const char *index_name,
+                                        bool *is_automatic)
 {
   rocksdb::ColumnFamilyHandle* cf_handle;
   ColumnFamilyHandleMap::iterator it;
 
   mysql_mutex_lock(&cfm_mutex);
-  if (name == NULL)
+  *is_automatic= false;
+  if (cf_name == NULL)
   {
     cf_handle= default_cf;
   }
-  else if ((it= cf_map.find(name)) != cf_map.end())
-    cf_handle= it->second;
   else
   {
-    /* Create a Column Family. */
-    std::string cf_name(name);
-    rocksdb::ColumnFamilyOptions opts;
-    get_cf_options(cf_name, &opts);
-
-    sql_print_information("RocksDB: creating column family %s", cf_name.c_str());
-    sql_print_information("    write_buffer_size=%ld",    opts.write_buffer_size);
-    sql_print_information("    target_file_size_base=%d", opts.target_file_size_base);
-
-    rocksdb::Status s= rdb->CreateColumnFamily(opts, name, &cf_handle);
-    if (s.ok())
-      cf_map[cf_name]= cf_handle;
+    std::string per_index_name;
+    if (!strcmp(cf_name, PER_INDEX_CF_NAME))
+    {
+      get_per_index_cf_name(db_table_name, index_name, &per_index_name);
+      cf_name= per_index_name.c_str();
+      *is_automatic= true;
+    }
+
+    if ((it= cf_map.find(cf_name)) != cf_map.end())
+      cf_handle= it->second;
     else
-      cf_handle= NULL;
+    {
+      /* Create a Column Family. */
+      std::string cf_name_str(cf_name);
+      rocksdb::ColumnFamilyOptions opts;
+      get_cf_options(cf_name_str, &opts);
+
+      sql_print_information("RocksDB: creating column family %s", cf_name_str.c_str());
+      sql_print_information("    write_buffer_size=%ld",    opts.write_buffer_size);
+      sql_print_information("    target_file_size_base=%d", opts.target_file_size_base);
+
+      rocksdb::Status s= rdb->CreateColumnFamily(opts, cf_name_str, &cf_handle);
+      if (s.ok())
+        cf_map[cf_name_str]= cf_handle;
+      else
+        cf_handle= NULL;
+    }
   }
   mysql_mutex_unlock(&cfm_mutex);
 
   return cf_handle;
 }
 
 
+/*
+  Find column family by its cf_name.
+
+  @detail
+  dbname.tablename  and index_name are also parameters, because
+  cf_name=PER_INDEX_CF_NAME means that column family name is a function
+  of table/index name.
+
+  @param out is_automatic  TRUE<=> column family name is auto-assigned based on
+                           db_table_name and index_name.
+*/
+
 rocksdb::ColumnFamilyHandle*
-Column_family_manager::get_cf(const char *name)
+Column_family_manager::get_cf(const char *cf_name,
+                              const char *db_table_name,
+                              const char *index_name,
+                              bool *is_automatic)
 {
   rocksdb::ColumnFamilyHandle* cf_handle;
   ColumnFamilyHandleMap::iterator it;
 
+  *is_automatic= false;
   mysql_mutex_lock(&cfm_mutex);
-  if (name == NULL)
+  if (cf_name == NULL)
     cf_handle= default_cf;
-  else if ((it= cf_map.find(name)) != cf_map.end())
-    cf_handle= it->second;
   else
-    cf_handle= NULL;
+  {
+    std::string per_index_name;
+    if (!strcmp(cf_name, PER_INDEX_CF_NAME))
+    {
+      get_per_index_cf_name(db_table_name, index_name, &per_index_name);
+      cf_name= per_index_name.c_str();
+      *is_automatic= true;
+    }
+
+    if ((it= cf_map.find(cf_name)) != cf_map.end())
+      cf_handle= it->second;
+    else
+      cf_handle= NULL;
+  }
   mysql_mutex_unlock(&cfm_mutex);
 
   return cf_handle;

storage/rocksdb/rdb_cf_manager.h

@@ -22,6 +22,9 @@
 */
 void get_cf_options(const std::string &cf_name, rocksdb::ColumnFamilyOptions *opts);
 
+void get_per_index_cf_name(const char *db_table_name, const char *index_name,
+                           std::string *res);
+
 /*
   We need a column family manager. Its functions:
   - create column families (synchronized, don't create the same twice)
@@ -54,12 +57,22 @@ class Column_family_manager
             std::vector<rocksdb::ColumnFamilyHandle*> *handles);
   void cleanup();
 
-  /* Used by CREATE TABLE. name=NULL means use default column family */
+  /*
+    Used by CREATE TABLE.
+    - cf_name=NULL means use default column family
+    - cf_name=_auto_ means use 'dbname.tablename.indexname'
+  */
   rocksdb::ColumnFamilyHandle* get_or_create_cf(rocksdb::DB *rdb,
-                                                const char *name);
+                                                const char *cf_name,
+                                                const char *db_table_name,
+                                                const char *index_name,
+                                                bool *is_automatic);
 
   /* Used by table open */
-  rocksdb::ColumnFamilyHandle* get_cf(const char *name);
+  rocksdb::ColumnFamilyHandle* get_cf(const char *cf_name,
+                                      const char *db_table_name,
+                                      const char *index_name,
+                                      bool *is_automatic);
 
   // void drop_cf(); -- not implemented so far.
 };

storage/rocksdb/rdb_datadic.cc

@@ -949,7 +949,8 @@ bool Table_ddl_manager::init(rocksdb::DB *rdb_dict)
         initialization requires that there is an open TABLE* where we could
         look at Field* objects and set max_length and other attributes
       */
-      tdef->key_descr[keyno]= new RDBSE_KEYDEF(index_number, keyno, NULL);
+      tdef->key_descr[keyno]= new RDBSE_KEYDEF(index_number, keyno, NULL,
+                                               false);
 
       /* Keep track of what was the last index number we saw */
       if (max_number < index_number)

storage/rocksdb/rdb_datadic.h

@@ -189,9 +189,10 @@ class RDBSE_KEYDEF
   }
 
   RDBSE_KEYDEF(uint indexnr_arg, uint keyno_arg,
-               rocksdb::ColumnFamilyHandle* cf_handle_arg) :
+               rocksdb::ColumnFamilyHandle* cf_handle_arg, bool is_auto_cf_arg) :
     index_number(indexnr_arg),
     cf_handle(cf_handle_arg),
+    is_auto_cf(is_auto_cf_arg),
     pk_part_no(NULL),
     pack_info(NULL),
     keyno(keyno_arg),
@@ -208,9 +209,11 @@ class RDBSE_KEYDEF
   };
 
   void setup(TABLE *table);
-  void set_cf_handle(rocksdb::ColumnFamilyHandle* cf_handle_arg)
+  void set_cf_handle(rocksdb::ColumnFamilyHandle* cf_handle_arg,
+                     bool is_auto_cf_arg)
   {
     cf_handle= cf_handle_arg;
+    is_auto_cf= is_auto_cf_arg;
   }
 
   rocksdb::ColumnFamilyHandle *get_cf() { return cf_handle; }
@@ -223,6 +226,9 @@ class RDBSE_KEYDEF
   uchar index_number_storage_form[INDEX_NUMBER_SIZE];
 
   rocksdb::ColumnFamilyHandle* cf_handle;
+public:
+  bool is_auto_cf;
+private:
 
   friend class RDBSE_TABLE_DEF; // for index_number above