SymbianOS Series 60学习笔记三：数据库初探

Series 60 中Symbian OS提供了一个数据库引擎

使用的时候需要用到库edbms.lib efsrv.lib

包含头文件d32dbms.h f32file.h

设置数据库文件路径

_LIT(KFileName,"c:\\test.db");

1. 建立一个数据库文件：

//建立表的sql语句

_LIT(KSQLCreateTable, "CREATE TABLE notesEntry(id COUNTER,note varchar,alarm varchar,private varchar)");

RFs fsSession = iEikonEnv->FsSession();

RDbNamedDatabase database;

User::LeaveIfError(fsSession.Connect());

User::LeaveIfError(database.Create(fsSession, KFileName));

User::LeaveIfError(database.Execute(KSQLCreateTable));

database.Close();

fsSession.Close();

2.插入或修改记录

//sql语句

_LIT(KSQL, "Insert into notesEntry(note,alarm ,private) values('s','s','s')");

或者

_LIT(KSQL, "update notesEntry set note = '90' ");

RDbs rdbs;

RDbNamedDatabase database;

User::LeaveIfError(rdbs.Connect());

User::LeaveIfError(database.Open(rdbs,KFileName));

User::LeaveIfError(database.Execute(KSQL));

database.Close();

rdbs.Close();

3.查看记录

_LIT(KSQLQueryTable, "Select id,note,alarm ,private from notesEntry");

RDbs rdbs;

RDbNamedDatabase database;

User::LeaveIfError(rdbs.Connect());

User::LeaveIfError(database.Open(rdbs,KFileName));

RDbView view;

User::LeaveIfError(view.Prepare(database,TDbQuery(KSQLQueryTable,EDbCompareNormal)));

User::LeaveIfError(view.EvaluateAll());

for (view.FirstL();view.AtRow();view.NextL())

{

view.GetL();

TUint32 id=view.ColUint32(1);

}

view.Close();

database.Close();

rdbs.Close();