diff options
Diffstat (limited to 'sql/sql_class.cc')
| -rw-r--r-- | sql/sql_class.cc | 157 |
1 files changed, 141 insertions, 16 deletions
diff --git a/sql/sql_class.cc b/sql/sql_class.cc index f8b2efe911c..7a4f3dff845 100644 --- a/sql/sql_class.cc +++ b/sql/sql_class.cc @@ -82,11 +82,84 @@ extern "C" void free_user_var(user_var_entry *entry) } +bool key_part_spec::operator==(const key_part_spec& other) const +{ + return length == other.length && !strcmp(field_name, other.field_name); +} + + +/* + Test if a foreign key (= generated key) is a prefix of the given key + (ignoring key name, key type and order of columns) + + NOTES: + This is only used to test if an index for a FOREIGN KEY exists + + IMPLEMENTATION + We only compare field names + + RETURN + 0 Generated key is a prefix of other key + 1 Not equal +*/ + +bool foreign_key_prefix(Key *a, Key *b) +{ + /* Ensure that 'a' is the generated key */ + if (a->generated) + { + if (b->generated && a->columns.elements > b->columns.elements) + swap_variables(Key*, a, b); // Put shorter key in 'a' + } + else + { + if (!b->generated) + return TRUE; // No foreign key + swap_variables(Key*, a, b); // Put generated key in 'a' + } + + /* Test if 'a' is a prefix of 'b' */ + if (a->columns.elements > b->columns.elements) + return TRUE; // Can't be prefix + + List_iterator<key_part_spec> col_it1(a->columns); + List_iterator<key_part_spec> col_it2(b->columns); + const key_part_spec *col1, *col2; + +#ifdef ENABLE_WHEN_INNODB_CAN_HANDLE_SWAPED_FOREIGN_KEY_COLUMNS + while ((col1= col_it1++)) + { + bool found= 0; + col_it2.rewind(); + while ((col2= col_it2++)) + { + if (*col1 == *col2) + { + found= TRUE; + break; + } + } + if (!found) + return TRUE; // Error + } + return FALSE; // Is prefix +#else + while ((col1= col_it1++)) + { + col2= col_it2++; + if (!(*col1 == *col2)) + return TRUE; + } + return FALSE; // Is prefix +#endif +} + + /**************************************************************************** ** Thread specific functions ****************************************************************************/ -THD::THD():user_time(0), current_statement(0), is_fatal_error(0), +THD::THD():user_time(0), current_arena(0), is_fatal_error(0), last_insert_id_used(0), insert_id_used(0), rand_used(0), in_lock_tables(0), global_read_lock(0), bootstrap(0), spcont(NULL) @@ -447,6 +520,35 @@ bool THD::convert_string(LEX_STRING *to, CHARSET_INFO *to_cs, /* + Convert string from source character set to target character set inplace. + + SYNOPSIS + THD::convert_string + + DESCRIPTION + Convert string using convert_buffer - buffer for character set + conversion shared between all protocols. + + RETURN + 0 ok + !0 out of memory +*/ + +bool THD::convert_string(String *s, CHARSET_INFO *from_cs, CHARSET_INFO *to_cs) +{ + if (convert_buffer.copy(s->ptr(), s->length(), from_cs, to_cs)) + return TRUE; + /* If convert_buffer >> s copying is more efficient long term */ + if (convert_buffer.alloced_length() >= convert_buffer.length() * 2 || + !s->is_alloced()) + { + return s->copy(convert_buffer); + } + s->swap(convert_buffer); + return FALSE; +} + +/* Update some cache variables when character set changes */ @@ -1210,23 +1312,47 @@ int select_dumpvar::prepare(List<Item> &list, SELECT_LEX_UNIT *u) } +Item_arena::Item_arena(THD* thd) + :free_list(0) +{ + init_sql_alloc(&mem_root, + thd->variables.query_alloc_block_size, + thd->variables.query_prealloc_size); +} + + +Item_arena::Item_arena() + :free_list(0) +{ + bzero((char *) &mem_root, sizeof(mem_root)); +} + + +Item_arena::Item_arena(bool init_mem_root) + :free_list(0) +{ + if (init_mem_root) + bzero((char *) &mem_root, sizeof(mem_root)); +} + + +Item_arena::~Item_arena() +{} + + /* Statement functions */ Statement::Statement(THD *thd) - :id(++thd->statement_id_counter), + :Item_arena(thd), + id(++thd->statement_id_counter), set_query_id(1), allow_sum_func(0), lex(&main_lex), query(0), - query_length(0), - free_list(0) -{ - init_sql_alloc(&mem_root, - thd->variables.query_alloc_block_size, - thd->variables.query_prealloc_size); -} + query_length(0) +{} /* This constructor is called when statement is a subobject of THD: @@ -1235,15 +1361,14 @@ Statement::Statement(THD *thd) */ Statement::Statement() - :id(0), + :Item_arena(), + id(0), set_query_id(1), allow_sum_func(0), /* initialized later */ lex(&main_lex), query(0), /* these two are set */ - query_length(0), /* in alloc_query() */ - free_list(0) + query_length(0) /* in alloc_query() */ { - bzero((char *) &mem_root, sizeof(mem_root)); } @@ -1264,14 +1389,14 @@ void Statement::set_statement(Statement *stmt) } -void Statement::set_n_backup_item_arena(Statement *set, Statement *backup) +void Item_arena::set_n_backup_item_arena(Item_arena *set, Item_arena *backup) { backup->set_item_arena(this); set_item_arena(set); } -void Statement::restore_backup_item_arena(Statement *set, Statement *backup) +void Item_arena::restore_backup_item_arena(Item_arena *set, Item_arena *backup) { set->set_item_arena(this); set_item_arena(backup); @@ -1279,7 +1404,7 @@ void Statement::restore_backup_item_arena(Statement *set, Statement *backup) init_alloc_root(&backup->mem_root, 0, 0); } -void Statement::set_item_arena(Statement *set) +void Item_arena::set_item_arena(Item_arena *set) { mem_root= set->mem_root; free_list= set->free_list; |