1.Each query has to check each row’s version numbers against the transaction’s version。
2.InnoDB must examine each row to ensure that it meets two criteria。innodb会根据以下两个条件检查每行记录
3.A live checksum of the entire table’s contents, if enabled。
4.MySQL 5.6 lab previews and milestone releases include a remarkable palette of new features for InnoDB, too.
5.you must alter the table with new values for the MAX_ROWS and AVG_ROW_LENGTH options that represent ballpark figures for
the amount of space you need. This will cause the entire table and all of its indexes to be rewritten, which might take a long time.谨慎操作
6.MyISAM supports full-text indexes, which index individual words for complex search operations.
7.You can configure delayed key writes globally, as well as for individual tables.
8.The rows are compressed individually, so MySQL doesn’t need to unpack an entire table (or even a page) just to fetch a single row.
9.This can boost performance, but after a server or system crash, the indexes will definitely be corrupted and will need repair.
10.although you can uncompress, modify, and recompress tables if you need to.
11.If your queries are all getting stuck in the “Locked” status,you’re suffering from table-level locking.
12.TokuDB uses a new index data structure called Fractal Trees, which are cacheoblivious,so they don’t slow down as they get
larger than memory, nor do they age or fragment.
13.TokuDB is marketed as a Big Data storage engine, because it has high compression ratios and can support lots of indexes
on large data volumes.
吃肉吐骨头--select * 与select col---select *不吐骨头，select col吐骨头，数据整行被加载到内存，select col只传输投影列
14.MySQL is row-oriented by default, meaning that each row’s data is stored together,and the server works in units of rows as it executes queries
15.We can name dozens of situations where InnoDB leaves MyISAM in the dust MyISAM望尘莫及
16.This release was the first under Sun Microsystems’s ownership after its acquisition of MySQL AB, and was over five years in the making.
17.it was clearly a disruptive innovation6 early in its lifecycle, with limited and sometimes second-class functionality, but its features
and low price made it a killer application to power the explosion of the Internet
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