big_optimizations_有道手机词典

1.The CHAR data type provides a performance boost because the database knows exactly how big every CHAR column will be and can make certain performance optimizations when reading or writing the data.
CHAR数据类型有助于性能提高，因为数据库确切地知道每个char列有多大，所以在读写数据时就可以执行某种性能优化。
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