2022-12-06 mysql-innodb引擎-核心数据结构

摘要:

innodb引擎很有意思, 将索引当作核心数据结构. 尤其是对于聚簇索引, 数据就是索引, 索引就是数据. 

在彻底解决innodb引擎的设计思想之前, 有必要将核心的数据结构进行说明.

page相关:

page0types.h

/* Type of the index page */
/* The following define eliminates a name collision on HP-UX */
#define page_t     ib_page_t
typedef	byte		page_t;
typedef struct page_search_struct	page_search_t;
typedef struct page_cur_struct	page_cur_t;

page_cur_struct

/* Index page cursor */
 
struct page_cur_struct{
	byte*	rec;	/* pointer to a record on page */
};

buf相关:

buf0types.h

mem_block_info_struct

/* The info header of a block in a memory heap */
 
struct mem_block_info_struct {
	ulint   magic_n;/* magic number for debugging */
	char	file_name[8];/* file name where the mem heap was created */
	ulint	line;	/* line number where the mem heap wa