请问各位高手,QT4中怎么连接MS SQL SERVER啊?

scse38060414 2010-10-22 08:04:30
以前用的是MYSQL。刚上手MS SQL SERVER,发现好麻烦啊,请问各位高手教教小弟怎么连接啊?
#include <QCoreApplication>
#include <QSqlDatabase>
#include <QSqlError>
#include <QDebug>
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
QString dsn = QString("Driver={sql server};server=CLOUDY-PC\SQLEXPRESS;database=qp;uid=sa;pwd=cloudy;");
QSqlDatabase db = QSqlDatabase::addDatabase("QODBC" , "db");
if(!db.open())
QSqlError error = db.lastError();
db.setPort(1433);;
db.setDatabaseName(dsn);
db.setUserName("sa");
db.setPassword("cloudy");
if(!db.open())
QSqlError error = db.lastError();
return a.exec();
}
如图啊,我想连到qp这个数据库,请问各位大侠怎么改?
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panda20184 2010-11-11
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我今天刚连成功:
#include <QSqlDatabase>
#include <QSqlError>
...
QSqlDatabase db = QSqlDatabase::addDatabase("QODBC");
db.setDatabaseName(QString("DRIVER={SQL SERVER};"
"SERVER=%1;"
"DATABASE=%2;"
"UID=%3;"
"PWD=%4;"
).arg(".") //可以的服务名:(local) loaclhost
.arg("JCZD")
.arg("hskj")
.arg("newtech") );
if(!db.open())
{
QMessageBox::critical(0,"Database error",db.lastError().text());
return;
}
....
yanj20 2010-10-25
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上面有个贴问连接Oracle的,再复制一下,
QT用的是C++标准,你可以直接使用SQLAPI++,SQLAPI++能够访问的数据去包括Oracle,SQLServer,DB2,Sybase,Informix,InterBase,SQLBase,MySQL,PostgreSQL,并且是标准的C++库。
SQLAPI++的官方网站是www.sqlapi.com
scse38060414 2010-10-22
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scse38060414 2010-10-22
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sql最全的常用命令语句 询某个数据库的连接数 select count(*) from Master.dbo.SysProcesses where dbid=db_id() --前10名其他等待类型 SELECT TOP 10 * from sys.dm_os_wait_stats ORDER BY wait_time_ms DESC SELECT *FROM sys.dm_os_wait_stats WHERE wait_type like 'PAGELATCH%' OR wait_type like 'LAZYWRITER_SLEEP%' --CPU的压力 SELECT scheduler_id, current_tasks_count, runnable_tasks_count FROM sys.dm_os_schedulers WHERE scheduler_id < 255 --表现最差的前10名使用查询 SELECT TOP 10 ProcedureName = t.text, ExecutionCount = s.execution_count, AvgExecutionTime = isnull ( s.total_elapsed_time / s.execution_count, 0 ), AvgWorkerTime = s.total_worker_time / s.execution_count, TotalWorkerTime = s.total_worker_time, MaxLogicalReads = s.max_logical_reads, MaxPhysicalReads = s.max_physical_reads, MaxLogicalWrites = s.max_logical_writes, CreationDateTime = s.creation_time, CallsPerSecond = isnull ( s.execution_count / datediff ( second , s.creation_time, getdate ()), 0 ) FROM sys.dm_exec_query_stats s CROSS APPLY sys.dm_exec_sql_text( s.sql_handle ) t ORDER BY s.max_physical_reads DESC SELECT SUM(signal_wait_time_ms) AS total_signal_wait_time_ms总信号等待时间 , SUM(wait_time_ms - signal_wait_time_ms) AS resource_wait_time_ms资源的等待时间, SUM(signal_wait_time_ms) * 1.0 / SUM (wait_time_ms) * 100 AS [signal_wait_percent信号等待%], SUM(wait_time_ms - signal_wait_time_ms) * 1.0 / SUM (wait_time_ms) * 100 AS [resource_wait_percent资源等待%] FROM sys.dm_os_wait_stats --一个信号等待时间过多对资源的等待时间那么你的CPU是目前的一个瓶颈。 --查看进程所执行的SQL语句 if (select COUNT(*) from master.dbo.sysprocesses) > 500 begin select text,CROSS APPLY master.sys.dm_exec_sql_text(a.sql_handle) from master.sys.sysprocesses a end select text,a.* from master.sys.sysprocesses a CROSS APPLY master.sys.dm_exec_sql_text(a.sql_handle) where a.spid = '51' dbcc inputbuffer(53) with tb as ( select blocking_session_id, session_id,db_name(database_id) as dbname,text from master.sys.dm_exec_requests a CROSS APPLY master.sys.dm_exec_sql_text(a.sql_handle) ), tb1 as ( select a.*,login_time,program_name,client_interface_name,login_name,cpu_time,memory_usage*8 as 'memory_usage(KB)', total_scheduled_time,reads,writes,logical_reads from tb a inner join master.sys.dm_exec_sessions b on a.session_id=b.session_id ) select a.*,connect_time,client_tcp_port,client_net_address from tb1 a inner join master.sys.dm_exec_connections b on a.session_id=b.session_id --当前进程数 select * from master.dbo.sysprocesses order by cpu desc --查看当前活动的进程数 sp_who active --查询是否由于连接没有释放引起CPU过高 select * from master.dbo.sysprocesses where spid> 50 and waittype = 0x0000 and waittime = 0 and status = 'sleeping ' and last_batch < dateadd(minute, -10, getdate()) and login_time < dateadd(minute, -10, getdate()) --强行释放空连接 select 'kill ' + rtrim(spid) from master.dbo.sysprocesses where spid> 50 and waittype = 0x0000 and waittime = 0 and status = 'sleeping ' and last_batch < dateadd(minute, -60, getdate()) and login_time < dateadd(minute, -60, getdate()) --查看当前占用 cpu 资源最高的会话和其执行的语句(及时CPU) select spid,cmd,cpu,physical_io,memusage, (select top 1 [text] from ::fn_get_sql(sql_handle)) sql_text from master..sysprocesses order by cpu desc,physical_io desc --查看缓存重用次数少,占用内存大的查询语句(当前缓存未释放的)--全局 SELECT TOP 100 usecounts, objtype, p.size_in_bytes,[sql].[text] FROM sys.dm_exec_cached_plans p OUTER APPLY sys.dm_exec_sql_text (p.plan_handle) sql ORDER BY usecounts,p.size_in_bytes desc SELECT top 25 qt.text,qs.plan_generation_num,qs.execution_count,dbid,objectid FROM sys.dm_exec_query_stats qs CROSS APPLY sys.dm_exec_sql_text(sql_handle) as qt WHERE plan_generation_num >1 ORDER BY qs.plan_generation_num SELECT top 50 qt.text AS SQL_text ,SUM(qs.total_worker_time) AS total_cpu_time, SUM(qs.execution_count) AS total_execution_count, SUM(qs.total_worker_time)/SUM(qs.execution_count) AS avg_cpu_time, COUNT(*) AS number_of_statements FROM sys.dm_exec_query_stats qs CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) as qt GROUP BY qt.text ORDER BY total_cpu_time DESC --统计总的CPU时间 --ORDER BY avg_cpu_time DESC --统计平均单次查询CPU时间 -- 计算可运行状态下的工作进程数量 SELECT COUNT(*) as workers_waiting_for_cpu,s.scheduler_id FROM sys.dm_os_workers AS o INNER JOIN sys.dm_os_schedulers AS s ON o.scheduler_address=s.scheduler_address AND s.scheduler_id<255 WHERE o.state='RUNNABLE' GROUP BY s.scheduler_id
m_pDbProcPic = new CDBProcess("sqlserver"); m_pDbProc->openDB("mysvr", "mydb", "myusername", "mypwd"); m_pDbProcPic = new CDBProcess("mysql"); m_pDbProc->openDB("localhost", "mydb", "root", "password"); m_pDbProcPic = new CDBProcess("access"); m_pDbProc->openDB("", strMDB, "sa", "password"); m_pDbProcPic = new CDBProcess("sqlite"); m_pDbProcPic->openDB("", "mysqlitedb"); CDBProcess使用说明 构造函数: CDBProcess(const QString strType); 参数:为数据库类型,不区分大小写,支持的类型有 sqlite mysql access sqlserver 例: CDBProcess db("sqlite"); -------------------------------------------------- 打开数据库 bool openDB(const QString strSvrName, //服务器名 const QString strDBname, //数据库名 const QString strUserID="", //用户名 const QString strUserPwd=""); //密码 打开数据库成功,返回true,否则返回false 对于sqlite,只有strDBname有效,其它参数忽略,如db.openDB("", "mysqlite.db") 对于MS Access数据库,strSvrName为空,用户名默认为"sa",如db.openDB("", "myaccess.mdb"); 对MSAccess数据库,也可通过一个UDL文件,打开,如db.openDB("my.udl", ""); mysqlsqlserver,就是各个参数依次提供,如db.openDB("svr1", "mydb", "user1", "abcd"); ----------------------------------------------------- 关闭数据库,CDBProcess析构时,亦会自动关闭数据库 void closeDB(); //db.closeDB(); ------------------------------------------------------ 执行Sql语句 bool excuteSQL(const QString); ------------------------------------------------------- 打开记录集 bool openRecordsetBySql(const QString strSql, //Sql语句 int idx = -1); //记录集id,用于标识记录集,默认值为-1 例: db.openRecordsetBySql("SELECT * FROM TB1", 5); 打开一个记录集,标识号为5,后面操作这个记录集,也要提供这个标识号 -------------------------------------------------------- 关闭记录集 void closeRecordset(int idx = -1); 例: db.closeRecordset(5); 关闭之前打开的标识为5的记录集 ----------------------------------- 数据库是否处在打开状态 bool isOpen() const; ------------------------------------ 记录集游标是否在结尾,参数为记录集标识 bool recEOF(int idx = -1) const; 例:bool b = db.RecBOF(5); ------------------------------------ 记录集游标是否在第一条记录之前,参数为记录集标识 bool recBOF(int idx = -1) const; ---------------------------------------- 删除一个表 bool dropTable(const QString); --------------------------------------------- 读取标识为idx记录集的当前记录的各字段值,方法如示例: bool getFieldsValueFromRec(int idx, const char* szFldInfo, ...) const; int iSN; QString strName; double dHeight; QDateTime dt; QByteArray ba; db.getFieldsValueFromRec(5, //记录集id "sn%d", &iSN, //字段名加类型 sn为字段名%d表示整型,&iSN传入指针,保存返回字段值 "name%s", &strName, //字段名加类型 name为字段名%s表示字符串(QString) "height&f", &dHeight, //字段名加类型 height为字段名%f表示小数(double) "birthday%t", &dt, //字段名加类型 birthday为字段名%t表示时间(QDateTime) "photo%b", &ba, //字段名加类型 photo为字段名%b表示二进制流(QByteArray) CDBProcess::szEnd); //结束标志,"|" 执行后,各字段值就保存在iSN, strName等变量了。 参数:第一个参数为记录集id 后面可变参数,字段%类型标识,用于保存返回值的指针, 类型标识:%d-int %s-QString %f-double %t-QDateTime %b-QByteArray --------------------------------------------------------------------------- 向一个数据表填加一条记录 bool addFieldsValueToTbl(const QString strTbl, const char* szFldInfo, ...); 参数:第一个参数strTbl,为表名 后面是可变参数,为"字段%类型标识",值(或指针),注int,double类型直接传值,其它传指针 例: db.addFieldsValueToTbl("TB1", //表名 "sn%d", iSN, //字段名加类型 sn为字段名%d表示整型,iSN传入值 "name%s", &strName, //字段名加类型 name为字段名%s表示字符串(QString), 传入QString变量指针 "height&f", dHeight, //字段名加类型 height为字段名%f表示小数(double),dHeight传入值 "birthday%t", &dt, //字段名加类型 birthday为字段名%t表示时间(QDateTime),传入指针 "photo%b", &ba, //字段名加类型 photo为字段名%b表示二进制流(QByteArray),传入指针 CDBProcess::szEnd); //结束标志,"|" ----------------------------------------------------------- 修改表符合WHERE子句条件的记录 bool updateTblFieldsValue(const QString strTbl, QString strWhere, const char * szFldInfo, ... ); strTbl表名 strWhere SQL WHERE子句,如"WHERE sn=20" const char * szFldInfo, ...可变参数,同addFieldsValueToTbl 例: db.updateTblFieldsValue("TB1", "WHERE sn=20", "height&f", dHeight, "photo%b", &ba, CDBProcess::szEnd); ---------------------------------------------------------------- 以下几个函数分别是获取记录数,和记录光标移动。参数为记录集标识 long getRecordCount(int idx = -1) const; bool moveFirst(int idx = -1) const; bool movePrevious(int idx = -1) const; bool moveNext(int idx = -1) const; bool moveLast(int idx = -1) const; bool moveTo(int n, int idx = -1) const; -------------------------------------------------------------------- 返回数据库名 QString getDbName() const; ------------------------ 以下几个函数未验证 bool execStoreProcOfArgList(int idx, const QString strStoreProc, const char* szFldsInfo, ...); bool exexProc(const QString strStoreProc, QString str1, QString& str2); bool transaction(); bool commit(); bool rollback();

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