Loading half a billion rows into MySQL—转载
BackgroundWe have a legacy system in our production environment that keeps track of when a user takes an action on Causes.com (joins a Cause, recruits a friend, etc). I say legacy, but I really mean a prematurely-optimized system that I’d
mysql Integer Types (Exact Value) – INTEGER, INT, SMALLINT,
使用mysql的时候，用到int类型的蛮多，需要注意一下：1. 值的范围TypeStorageMinimum ValueMaximum Value(Bytes)(Signed/Unsigned)(Signed/Unsigned)TINYINT1-128127255SMALLINT2-327683276765535MEDIUMINT3-8388608838860716777215INT4-21474836482147483647
mybatis中#{}和${}的区别
mybatis本身的说明：String SubstitutionBy default, using the #{} syntax will cause MyBatis to generate PreparedStatement properties and set the values safely against the PreparedStatement parameters (e.g. ?). While this is safer, faster and
Python操作 RabbitMQ、Redis、Memcache、SQLAlchemy
divid=\cnblogs_post_body\class=\blogpost-body\MemcachedMemcached是一个高性能的分布式内存对象缓存系统，用于动态Web应用以减轻数据库负载。它通过在内存中缓存数据和对象来减
flask-sqlalchemy 一对一，一对多，多对多操作
先进行如下操作：fromflaskimportFlaskfromflask.ext.sqlalchemyimportSQLAlchemyapp=Flask(__name__)
索引长度过长 ERROR 1071 (42000): Specified key was too long; max k
divid=\article_content\class=\article_contentcsdn-tracking-statisticstracking-click\style=\overflow:hidden;\data-dsm=\post\data-mod=\popu_519\
sqlachemy 查询当日数据，
Tokens.query.filter(Tokens.user_id==user_id,db.cast(Tokens.create_time,db.DATE)==db.cast(current_time,db.DATE)).all()