• MySQL基本数据类型与Java基本数据类型



               早上写了篇博客,发现蛮有感觉的,工作了一整天,发现又有些东西可以写了,呵呵……  分享下……  微笑


               经过几天的Dao层和Service层代码的编写,今天终于到了看成果的时候了,把项目启动后,输入一个Url访问项目接口。糟糕,报错,没事,Dao层的错误,没问题,就是SQL的问题。说明下,我们公司操作数据库是用jdbc的,所有比较麻烦,但是效率相对来说是蛮高的。

              但是,我仔细对比了代码,没发现问题了,但总是抱 “Statement parameter 13 not set.” 错误。

             没办法,只能一步一步的找咯。我把Sql语句和各个参数都打印出来。然后放到SQLyog里去执行。没问题额。惊讶

            我把tomcat在次启动,访问接口,还是抱 “Statement parameter 13 not set.” 错误。我在仔细看了下,不会是关键字的问题了吧?唉……  试下呗,Pass 。哦,我焕然大雾,原来是类型不匹配,Java是short类型,mysql是tinyint类型。

           下面是我从网上找来的Java基本数据类型和mysql基本数据类型对照表:

    BIT(1) (new in MySQL-5.0) BIT java.lang.Boolean
    BIT( > 1) (new in MySQL-5.0) BIT byte[]
    TINYINT TINYINT java.lang.Boolean if the configuration property tinyInt1isBit is set to true (the default) and the storage size is 1, or java.lang.Integer if not.
    BOOL, BOOLEAN TINYINT See TINYINT, above as these are aliases for TINYINT(1), currently.
    SMALLINT[(M)] [UNSIGNED] SMALLINT [UNSIGNED] java.lang.Integer (regardless if UNSIGNED or not)
    MEDIUMINT[(M)] [UNSIGNED] MEDIUMINT [UNSIGNED] java.lang.Integer, if UNSIGNED java.lang.Long (C/J 3.1 and earlier), or java.lang.Integer for C/J 5.0 and later
    INT,INTEGER[(M)] [UNSIGNED] INTEGER [UNSIGNED] java.lang.Integer, if UNSIGNED java.lang.Long
    BIGINT[(M)] [UNSIGNED] BIGINT [UNSIGNED] java.lang.Long, if UNSIGNED java.math.BigInteger
    FLOAT[(M,D)] FLOAT java.lang.Float
    DOUBLE[(M,B)] DOUBLE java.lang.Double
    DECIMAL[(M[,D])] DECIMAL java.math.BigDecimal
    DATE DATE java.sql.Date
    DATETIME DATETIME java.sql.Timestamp
    TIMESTAMP[(M)] TIMESTAMP java.sql.Timestamp
    TIME TIME java.sql.Time
    YEAR[(2|4)] YEAR If yearIsDateType configuration property is set to false, then the returned object type is java.sql.Short. If set to true (the default) then an object of type java.sql.Date (with the date set to January 1st, at midnight).
    CHAR(M) CHAR java.lang.String (unless the character set for the column is BINARY, then byte[] is returned.
    VARCHAR(M) [BINARY] VARCHAR java.lang.String (unless the character set for the column is BINARY, then byte[] is returned.
    BINARY(M) BINARY byte[]
    VARBINARY(M) VARBINARY byte[]
    TINYBLOB TINYBLOB byte[]
    TINYTEXT VARCHAR java.lang.String
    BLOB BLOB byte[]
    TEXT VARCHAR java.lang.String
    MEDIUMBLOB MEDIUMBLOB byte[]
    MEDIUMTEXT VARCHAR java.lang.String
    LONGBLOB LONGBLOB byte[]
    LONGTEXT VARCHAR java.lang.String
    ENUM('value1','value2',...) CHAR java.lang.String
    SET('value1','value2',...) CHAR java.lang.String

    松下问童子,言师采药去。 只言此山中,云深不知处。
  • 相关阅读:
    SpringBoot中使用Redis
    SpringBoot中实现事务
    SpringBoot中集成持久层框架Mybatis
    JavaScript遍历数组、对象
    web面试(一)
    create-react-app初始化报错及配置less
    JavaScript异步(SuperAgent , isomorphic-fetch)
    JavaScript数组
    JavaScript(token,cookie)
    JavaScript时间段重叠
  • 原文地址:https://www.cnblogs.com/sten/p/5601872.html
Copyright © 2020-2023  润新知