首先要安装mysql驱动程序包,详细步骤如下:
Step 1:将mysql-connector-java-5.1.7-bin.jar文件拷贝到....../MATLAB/R2009a/java/jar/toolbox
Step 2:到....../MATLAB/R2009a/toolbox/local目录下,找到classpath.txt文件,打开,并添加用来加载mysql的jdbc驱动语句:
$matlabroot/java/jar/toolbox/mysql-connector-java-5.1.7-bin.jar
Step 3:重新打开MATLAB即可
驱动程序安装成功后,接来下要是matlab连接mysql数据库的代码:
conn=database('databasename','username','password','driver','databaseurl')
连接成功后,返回连接对象。
参数如下:*databasename: 数据库名称.
*driver: JDBC driver.
*username and password: 用户名和密码.
*databaseurl: 类似于jdbc:subprotocol:subname. subprotocol是数据库类型,
subname类似于//hostname:port/databasename.
如果matlab和数据库建立了连接,将返回类似于如下信息:
Instance: 'SampleDB' UserName: ''Driver: []URL: []Constructor: [1x1com.mathworks.toolbox.database.databaseConnect] Message: []Handle: [1x1 sun.jdbc.odbc.JdbcOdbcConnection] TimeOut: 0AutoCommit: 'off' Type: 'Database Object' |
连接mysql的代码如下:
conn = database('tissueppi','root','root','com.mysql.jdbc.Driver','jdbc:mysql://localhost:3306/tissueppi');
连接成功后,就可以用exec函数执行sql语句
exec函数执行sql语句并返回一个开指针
语法如下:curs =exec(conn,'sqlquery')
例如:curs = exec(conn, 'select * fromcustomers')
执行完查询后,还要将查询结果从开放cursor对象导入到对象curs中,该功能是用
cursor.fetch函数实现的。语法如下:
curs =fetch(curs)
使用curs.Data来显示数据,curs.Data返回一个CELL结构,可以先把CELL结构转换成
MATRIX结构再取值:
cur=cell2mat(cur)
a=cur(1,1);则查询结果就加到了向量a中
注意:在exec函数执行查询过程中,有的sql语句要输入变量,这时可使用strcat函数完成该
功能。
t =strcat(s1, s2, s3, ...) for(t=1:10)sql1 = strcat('select count(did) from rss_genepairs_u wheregocc>=',num2str(t),' || gomf>= ',num2str(t),' || gobp >=',num2str(t)); end |
conn =database('tissueppi','root','root','com.mysql.jdbc.Driver','jdbc:mysql://localhost:3306/tissueppi'); for t=0.5:0.01:0.91 for x=0.5:0.1:11 sql = strcat('select count(did) from rss_genepairs_x2 where score=',num2str(t),' || gomf>= ',num2str(t),' || gobp >=',num2str(t),')'); aTemp = exec(conn,sql); aTemp = fetch(aTemp); a = aTemp.Data; a = cell2mat(a); a= a(1,1);endend |

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