关注SQLite

好久没有关注SQLite,这两天忽然想到它,就来看看,没想到SQLite都已经更新了好几版了。今天下了个最新的源代码,编译试试,发现编译dll后没lib文件,这让我有点郁闷,我再把以前我编译过的版本拿出来看看,靠,新的源码中竟然没提供def文件,怪不得搞不出lib文件。没撤,只好google一下怎么搞出lib文件,以下是一种方法我们可以照葫芦画瓢。

来源于:http://www.jb51.cc/article/p-yciibesb-bqv.html

VC中使用sqlite
SQLite官方下载只提供给我们一个sqlite3.dll跟一个sqlite3.def文件,并没有提供用于VC++6.0的lib文件,可以利用sqlite3.def文件生成,步骤如下:
1.将sqlite3.h(D:\sqlite-amalgamation-3_6_23.zip)拷贝到C:\Program Files\Microsoft Visual Studio\VC98\Include目录下,这时编译可通过,但链接错误,因为没有LIB文件()
2.启动一个命令行程序,进入VC的安装目录C:\Program Files\Microsoft Visual Studio\VC98\Bin,在这个目录下面有一个LIB.exe文件,使用它就能生成sqlite3.lib文件,将sqlite3.def文件放到相同目录,或者绝对路径也可以, 然后在命令行输入如下命令:
LIB /MACHINE:IX86 /DEF:sqlite3.def
该命令生成两个文件:sqlite3.lib和sqlite3.exp
运行该命令时,如果提示找不到MSPDB60.DLL文件,可从其它目录拷贝至Bin目录下
3.将生成的sqlite3.lib拷贝到Lib目录下,将sqlite3.dll拷贝到C:\WINNT\system32目录下
4.将sqlite3.lib加入到工程链接中,Project->Settings,Link选项卡,Object/library modules最后添入sqlite3.lib
D:\sqlitedll-3_6_23里有.dll和.def文件
生成的lib在bin下

这里还有一篇http://www.jb51.cc/article/p-daizqzib-zk.html

SQLite毕竟是C的,我们使用起来比较麻烦不爽,现在都讲究面向对象,那我们就应该把它封装一下,唉,你想到的,别人早就做到了。这里有个SQLite C++的封装库,下载地址为http://www.sqlite.com.cn/MySqlite/7/95.Html

////////////////////////////////////////////////////////////////////////////////
// CppSQLite3 - A C++ wrapper around the SQLite3 embedded database library.
//
// Copyright (c) 2004 Rob Groves. All Rights Reserved. rob.groves@btinternet.com
// 
// Permission to use,copy,modify,and distribute this software and its
// documentation for any purpose,without fee,and without a written
// agreement,is hereby granted,provided that the above copyright notice,// this paragraph and the following two paragraphs appear in all copies,// modifications,and distributions.
//
// IN NO EVENT SHALL THE AUTHOR BE LIABLE TO ANY PARTY FOR DIRECT,// INDIRECT,SPECIAL,INCIDENTAL,OR CONSEQUENTIAL DAMAGES,INCLUDING LOST
// PROFITS,ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION,// EVEN IF THE AUTHOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// THE AUTHOR SPECIFICALLY DISCLAIMS ANY WARRANTIES,INCLUDING,BUT NOT
// LIMITED TO,THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
// PARTICULAR PURPOSE. THE SOFTWARE AND ACCOMPANYING DOCUMENTATION,IF
// ANY,PROVIDED HEREUNDER IS PROVIDED "AS IS". THE AUTHOR HAS NO OBLIGATION
// TO PROVIDE MAINTENANCE,SUPPORT,UPDATES,ENHANCEMENTS,OR MODIFICATIONS.
//
// V3.0		03/08/2004	-Initial Version for sqlite3
//
// V3.1		16/09/2004	-Implemented getXXXXField using sqlite3 functions
//						-Added CppSQLiteDB3::tableExists()
////////////////////////////////////////////////////////////////////////////////
#ifndef _CppSQLite3_H_
#define _CppSQLite3_H_

#include "sqlite3.h"
#include <cstdio>
#include <cstring>

#define CPPSQLITE_ERROR 1000

class CppSQLite3Exception
{
public:

    CppSQLite3Exception(const int nErrCode,char* szErrMess,bool bDeleteMsg=true);

    CppSQLite3Exception(const CppSQLite3Exception&  e);

    virtual ~CppSQLite3Exception();

    const int errorCode() { return mnErrCode; }

    const char* errorMessage() { return mpszErrMess; }

    static const char* errorCodeAsString(int nErrCode);

private:

    int mnErrCode;
    char* mpszErrMess;
};


class CppSQLite3Buffer
{
public:

    CppSQLite3Buffer();

    ~CppSQLite3Buffer();

    const char* format(const char* szFormat,...);

    operator const char*() { return mpBuf; }

    void clear();

private:

    char* mpBuf;
};


class CppSQLite3Binary
{
public:

    CppSQLite3Binary();

    ~CppSQLite3Binary();

    void setBinary(const unsigned char* pBuf,int nLen);
    void setEncoded(const unsigned char* pBuf);

    const unsigned char* getEncoded();
    const unsigned char* getBinary();

    int getBinaryLength();

    unsigned char* allocBuffer(int nLen);

    void clear();

private:

    unsigned char* mpBuf;
    int mnBinaryLen;
    int mnBufferLen;
    int mnEncodedLen;
    bool mbEncoded;
};


class CppSQLite3Query
{
public:

    CppSQLite3Query();

    CppSQLite3Query(const CppSQLite3Query& rQuery);

    CppSQLite3Query(sqlite3* pDB,sqlite3_stmt* pVM,bool bEof,bool bOwnVM=true);

    CppSQLite3Query& operator=(const CppSQLite3Query& rQuery);

    virtual ~CppSQLite3Query();

    int numFields();

    int fieldIndex(const char* szField);
    const char* fieldName(int nCol);

    const char* fieldDeclType(int nCol);
    int fieldDataType(int nCol);

    const char* fieldValue(int nField);
    const char* fieldValue(const char* szField);

    int getIntField(int nField,int nNullValue=0);
    int getIntField(const char* szField,int nNullValue=0);

    double getFloatField(int nField,double fNullValue=0.0);
    double getFloatField(const char* szField,double fNullValue=0.0);

    const char* getStringField(int nField,const char* szNullValue="");
    const char* getStringField(const char* szField,const char* szNullValue="");

    const unsigned char* getBlobField(int nField,int& nLen);
    const unsigned char* getBlobField(const char* szField,int& nLen);

    bool fieldIsNull(int nField);
    bool fieldIsNull(const char* szField);

    bool eof();

    void nextRow();

    void finalize();

private:

    void checkVM();

	sqlite3* mpDB;
    sqlite3_stmt* mpVM;
    bool mbEof;
    int mnCols;
    bool mbOwnVM;
};


class CppSQLite3Table
{
public:

    CppSQLite3Table();

    CppSQLite3Table(const CppSQLite3Table& rTable);

    CppSQLite3Table(char** paszResults,int nRows,int nCols);

    virtual ~CppSQLite3Table();

    CppSQLite3Table& operator=(const CppSQLite3Table& rTable);

    int numFields();

    int numRows();

    const char* fieldName(int nCol);

    const char* fieldValue(int nField);
    const char* fieldValue(const char* szField);

    int getIntField(int nField,const char* szNullValue="");

    bool fieldIsNull(int nField);
    bool fieldIsNull(const char* szField);

    void setRow(int nRow);

    void finalize();

private:

    void checkResults();

    int mnCols;
    int mnRows;
    int mnCurrentRow;
    char** mpaszResults;
};


class CppSQLite3Statement
{
public:

    CppSQLite3Statement();

    CppSQLite3Statement(const CppSQLite3Statement& rStatement);

    CppSQLite3Statement(sqlite3* pDB,sqlite3_stmt* pVM);

    virtual ~CppSQLite3Statement();

    CppSQLite3Statement& operator=(const CppSQLite3Statement& rStatement);

    int execDML();

    CppSQLite3Query execQuery();

    void bind(int nParam,const char* szValue);
    void bind(int nParam,const int nValue);
    void bind(int nParam,const double dwValue);
    void bind(int nParam,const unsigned char* blobValue,int nLen);
    void bindNull(int nParam);

    void reset();

    void finalize();

private:

    void checkDB();
    void checkVM();

    sqlite3* mpDB;
    sqlite3_stmt* mpVM;
};


class CppSQLite3DB
{
public:

    CppSQLite3DB();

    virtual ~CppSQLite3DB();

    void open(const char* szFile);

    void close();

	bool tableExists(const char* szTable);

    int execDML(const char* szSQL);

    CppSQLite3Query execQuery(const char* szSQL);

    int execScalar(const char* szSQL);

    CppSQLite3Table getTable(const char* szSQL);

    CppSQLite3Statement compileStatement(const char* szSQL);

    sqlite_int64 lastRowId();

    void interrupt() { sqlite3_interrupt(mpDB); }

    void setBusyTimeout(int nMillisecs);

    static const char* SQLiteVersion() { return SQLITE_VERSION; }

private:

    CppSQLite3DB(const CppSQLite3DB& db);
    CppSQLite3DB& operator=(const CppSQLite3DB& db);

    sqlite3_stmt* compile(const char* szSQL);

    void checkDB();

    sqlite3* mpDB;
    int mnBusyTimeoutMs;
};

#endif


////////////////////////////////////////////////////////////////////////////////
// CppSQLite3 - A C++ wrapper around the SQLite3 embedded database library.
//
// Copyright (c) 2004 Rob Groves. All Rights Reserved. rob.groves@btinternet.com
// 
// Permission to use,OR MODIFICATIONS.
//
// V3.0		03/08/2004	-Initial Version for sqlite3
//
// V3.1		16/09/2004	-Implemented getXXXXField using sqlite3 functions
//						-Added CppSQLiteDB3::tableExists()
////////////////////////////////////////////////////////////////////////////////
#include "CppSQLite3.h"
#include <cstdlib>


// Named constant for passing to CppSQLite3Exception when passing it a string
// that cannot be deleted.
static const bool DONT_DELETE_MSG=false;

////////////////////////////////////////////////////////////////////////////////
// Prototypes for SQLite functions not included in SQLite DLL,but copied below
// from SQLite encode.c
////////////////////////////////////////////////////////////////////////////////
int sqlite3_encode_binary(const unsigned char *in,int n,unsigned char *out);
int sqlite3_decode_binary(const unsigned char *in,unsigned char *out);

////////////////////////////////////////////////////////////////////////////////

////////////////////////////////////////////////////////////////////////////////

CppSQLite3Exception::CppSQLite3Exception(const int nErrCode,bool bDeleteMsg/*=true*/) :
									mnErrCode(nErrCode)
{
	mpszErrMess = sqlite3_mprintf("%s[%d]: %s",errorCodeAsString(nErrCode),nErrCode,szErrMess ? szErrMess : "");

	if (bDeleteMsg && szErrMess)
	{
		sqlite3_free(szErrMess);
	}
}

									
CppSQLite3Exception::CppSQLite3Exception(const CppSQLite3Exception&  e) :
									mnErrCode(e.mnErrCode)
{
	mpszErrMess = 0;
	if (e.mpszErrMess)
	{
		mpszErrMess = sqlite3_mprintf("%s",e.mpszErrMess);
	}
}


const char* CppSQLite3Exception::errorCodeAsString(int nErrCode)
{
	switch (nErrCode)
	{
		case SQLITE_OK          : return "SQLITE_OK";
		case SQLITE_ERROR       : return "SQLITE_ERROR";
		case SQLITE_INTERNAL    : return "SQLITE_INTERNAL";
		case SQLITE_PERM        : return "SQLITE_PERM";
		case SQLITE_ABORT       : return "SQLITE_ABORT";
		case SQLITE_BUSY        : return "SQLITE_BUSY";
		case SQLITE_LOCKED      : return "SQLITE_LOCKED";
		case SQLITE_NOMEM       : return "SQLITE_NOMEM";
		case SQLITE_READONLY    : return "SQLITE_READONLY";
		case SQLITE_INTERRUPT   : return "SQLITE_INTERRUPT";
		case SQLITE_IOERR       : return "SQLITE_IOERR";
		case SQLITE_CORRUPT     : return "SQLITE_CORRUPT";
		case SQLITE_NOTFOUND    : return "SQLITE_NOTFOUND";
		case SQLITE_FULL        : return "SQLITE_FULL";
		case SQLITE_CANTOPEN    : return "SQLITE_CANTOPEN";
		case SQLITE_PROTOCOL    : return "SQLITE_PROTOCOL";
		case SQLITE_EMPTY       : return "SQLITE_EMPTY";
		case SQLITE_SCHEMA      : return "SQLITE_SCHEMA";
		case SQLITE_TOOBIG      : return "SQLITE_TOOBIG";
		case SQLITE_CONSTRAINT  : return "SQLITE_CONSTRAINT";
		case SQLITE_MISMATCH    : return "SQLITE_MISMATCH";
		case SQLITE_MISUSE      : return "SQLITE_MISUSE";
		case SQLITE_NOLFS       : return "SQLITE_NOLFS";
		case SQLITE_AUTH        : return "SQLITE_AUTH";
		case SQLITE_FORMAT      : return "SQLITE_FORMAT";
		case SQLITE_RANGE       : return "SQLITE_RANGE";
		case SQLITE_ROW         : return "SQLITE_ROW";
		case SQLITE_DONE        : return "SQLITE_DONE";
		case CPPSQLITE_ERROR    : return "CPPSQLITE_ERROR";
		default: return "UNKNOWN_ERROR";
	}
}


CppSQLite3Exception::~CppSQLite3Exception()
{
	if (mpszErrMess)
	{
		sqlite3_free(mpszErrMess);
		mpszErrMess = 0;
	}
}


////////////////////////////////////////////////////////////////////////////////

CppSQLite3Buffer::CppSQLite3Buffer()
{
	mpBuf = 0;
}


CppSQLite3Buffer::~CppSQLite3Buffer()
{
	clear();
}


void CppSQLite3Buffer::clear()
{
	if (mpBuf)
	{
		sqlite3_free(mpBuf);
		mpBuf = 0;
	}

}


const char* CppSQLite3Buffer::format(const char* szFormat,...)
{
	clear();
	va_list va;
	va_start(va,szFormat);
	mpBuf = sqlite3_vmprintf(szFormat,va);
	va_end(va);
	return mpBuf;
}


////////////////////////////////////////////////////////////////////////////////

CppSQLite3Binary::CppSQLite3Binary() :
						mpBuf(0),mnBinaryLen(0),mnBufferLen(0),mnEncodedLen(0),mbEncoded(false)
{
}


CppSQLite3Binary::~CppSQLite3Binary()
{
	clear();
}


void CppSQLite3Binary::setBinary(const unsigned char* pBuf,int nLen)
{
	mpBuf = allocBuffer(nLen);
	memcpy(mpBuf,pBuf,nLen);
}


void CppSQLite3Binary::setEncoded(const unsigned char* pBuf)
{
	clear();

	mnEncodedLen = strlen((const char*)pBuf);
	mnBufferLen = mnEncodedLen + 1; // Allow for NULL terminator

	mpBuf = (unsigned char*)malloc(mnBufferLen);

	if (!mpBuf)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,"Cannot allocate memory",DONT_DELETE_MSG);
	}

	memcpy(mpBuf,mnBufferLen);
	mbEncoded = true;
}


const unsigned char* CppSQLite3Binary::getEncoded()
{
	if (!mbEncoded)
	{
		unsigned char* ptmp = (unsigned char*)malloc(mnBinaryLen);
		memcpy(ptmp,mpBuf,mnBinaryLen);
		mnEncodedLen = sqlite3_encode_binary(ptmp,mnBinaryLen,mpBuf);
		free(ptmp);
		mbEncoded = true;
	}

	return mpBuf;
}


const unsigned char* CppSQLite3Binary::getBinary()
{
	if (mbEncoded)
	{
		// in/out buffers can be the same
		mnBinaryLen = sqlite3_decode_binary(mpBuf,mpBuf);

		if (mnBinaryLen == -1)
		{
			throw CppSQLite3Exception(CPPSQLITE_ERROR,"Cannot decode binary",DONT_DELETE_MSG);
		}

		mbEncoded = false;
	}

	return mpBuf;
}


int CppSQLite3Binary::getBinaryLength()
{
	getBinary();
	return mnBinaryLen;
}


unsigned char* CppSQLite3Binary::allocBuffer(int nLen)
{
	clear();

	// Allow extra space for encoded binary as per comments in
	// SQLite encode.c See bottom of this file for implementation
	// of SQLite functions use 3 instead of 2 just to be sure ;-)
	mnBinaryLen = nLen;
	mnBufferLen = 3 + (257*nLen)/254;

	mpBuf = (unsigned char*)malloc(mnBufferLen);

	if (!mpBuf)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,DONT_DELETE_MSG);
	}

	mbEncoded = false;

	return mpBuf;
}


void CppSQLite3Binary::clear()
{
	if (mpBuf)
	{
		mnBinaryLen = 0;
		mnBufferLen = 0;
		free(mpBuf);
		mpBuf = 0;
	}
}


////////////////////////////////////////////////////////////////////////////////

CppSQLite3Query::CppSQLite3Query()
{
	mpVM = 0;
	mbEof = true;
	mnCols = 0;
	mbOwnVM = false;
}


CppSQLite3Query::CppSQLite3Query(const CppSQLite3Query& rQuery)
{
	mpVM = rQuery.mpVM;
	// Only one object can own the VM
	const_cast<CppSQLite3Query&>(rQuery).mpVM = 0;
	mbEof = rQuery.mbEof;
	mnCols = rQuery.mnCols;
	mbOwnVM = rQuery.mbOwnVM;
}


CppSQLite3Query::CppSQLite3Query(sqlite3* pDB,bool bOwnVM/*=true*/)
{
	mpDB = pDB;
	mpVM = pVM;
	mbEof = bEof;
	mnCols = sqlite3_column_count(mpVM);
	mbOwnVM = bOwnVM;
}


CppSQLite3Query::~CppSQLite3Query()
{
	try
	{
		finalize();
	}
	catch (...)
	{
	}
}


CppSQLite3Query& CppSQLite3Query::operator=(const CppSQLite3Query& rQuery)
{
	try
	{
		finalize();
	}
	catch (...)
	{
	}
	mpVM = rQuery.mpVM;
	// Only one object can own the VM
	const_cast<CppSQLite3Query&>(rQuery).mpVM = 0;
	mbEof = rQuery.mbEof;
	mnCols = rQuery.mnCols;
	mbOwnVM = rQuery.mbOwnVM;
	return *this;
}


int CppSQLite3Query::numFields()
{
	checkVM();
	return mnCols;
}


const char* CppSQLite3Query::fieldValue(int nField)
{
	checkVM();

	if (nField < 0 || nField > mnCols-1)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,"Invalid field index requested",DONT_DELETE_MSG);
	}

	return (const char*)sqlite3_column_text(mpVM,nField);
}


const char* CppSQLite3Query::fieldValue(const char* szField)
{
	int nField = fieldIndex(szField);
	return (const char*)sqlite3_column_text(mpVM,nField);
}


int CppSQLite3Query::getIntField(int nField,int nNullValue/*=0*/)
{
	if (fieldDataType(nField) == SQLITE_NULL)
	{
		return nNullValue;
	}
	else
	{
		return sqlite3_column_int(mpVM,nField);
	}
}


int CppSQLite3Query::getIntField(const char* szField,int nNullValue/*=0*/)
{
	int nField = fieldIndex(szField);
	return getIntField(nField,nNullValue);
}


double CppSQLite3Query::getFloatField(int nField,double fNullValue/*=0.0*/)
{
	if (fieldDataType(nField) == SQLITE_NULL)
	{
		return fNullValue;
	}
	else
	{
		return sqlite3_column_double(mpVM,nField);
	}
}


double CppSQLite3Query::getFloatField(const char* szField,double fNullValue/*=0.0*/)
{
	int nField = fieldIndex(szField);
	return getFloatField(nField,fNullValue);
}


const char* CppSQLite3Query::getStringField(int nField,const char* szNullValue/*=""*/)
{
	if (fieldDataType(nField) == SQLITE_NULL)
	{
		return szNullValue;
	}
	else
	{
		return (const char*)sqlite3_column_text(mpVM,nField);
	}
}


const char* CppSQLite3Query::getStringField(const char* szField,const char* szNullValue/*=""*/)
{
	int nField = fieldIndex(szField);
	return getStringField(nField,szNullValue);
}


const unsigned char* CppSQLite3Query::getBlobField(int nField,int& nLen)
{
	checkVM();

	if (nField < 0 || nField > mnCols-1)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,DONT_DELETE_MSG);
	}

	nLen = sqlite3_column_bytes(mpVM,nField);
	return (const unsigned char*)sqlite3_column_blob(mpVM,nField);
}


const unsigned char* CppSQLite3Query::getBlobField(const char* szField,int& nLen)
{
	int nField = fieldIndex(szField);
	return getBlobField(nField,nLen);
}


bool CppSQLite3Query::fieldIsNull(int nField)
{
	return (fieldDataType(nField) == SQLITE_NULL);
}


bool CppSQLite3Query::fieldIsNull(const char* szField)
{
	int nField = fieldIndex(szField);
	return (fieldDataType(nField) == SQLITE_NULL);
}


int CppSQLite3Query::fieldIndex(const char* szField)
{
	checkVM();

	if (szField)
	{
		for (int nField = 0; nField < mnCols; nField++)
		{
			const char* szTemp = sqlite3_column_name(mpVM,nField);

			if (strcmp(szField,szTemp) == 0)
			{
				return nField;
			}
		}
	}

	throw CppSQLite3Exception(CPPSQLITE_ERROR,"Invalid field name requested",DONT_DELETE_MSG);
}


const char* CppSQLite3Query::fieldName(int nCol)
{
	checkVM();

	if (nCol < 0 || nCol > mnCols-1)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,DONT_DELETE_MSG);
	}

	return sqlite3_column_name(mpVM,nCol);
}


const char* CppSQLite3Query::fieldDeclType(int nCol)
{
	checkVM();

	if (nCol < 0 || nCol > mnCols-1)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,DONT_DELETE_MSG);
	}

	return sqlite3_column_decltype(mpVM,nCol);
}


int CppSQLite3Query::fieldDataType(int nCol)
{
	checkVM();

	if (nCol < 0 || nCol > mnCols-1)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,DONT_DELETE_MSG);
	}

	return sqlite3_column_type(mpVM,nCol);
}


bool CppSQLite3Query::eof()
{
	checkVM();
	return mbEof;
}


void CppSQLite3Query::nextRow()
{
	checkVM();

	int nRet = sqlite3_step(mpVM);

	if (nRet == SQLITE_DONE)
	{
		// no rows
		mbEof = true;
	}
	else if (nRet == SQLITE_ROW)
	{
		// more rows,nothing to do
	}
	else
	{
		nRet = sqlite3_finalize(mpVM);
		mpVM = 0;
		const char* szError = sqlite3_errmsg(mpDB);
		throw CppSQLite3Exception(nRet,(char*)szError,DONT_DELETE_MSG);
	}
}


void CppSQLite3Query::finalize()
{
	if (mpVM && mbOwnVM)
	{
		int nRet = sqlite3_finalize(mpVM);
		mpVM = 0;
		if (nRet != SQLITE_OK)
		{
			const char* szError = sqlite3_errmsg(mpDB);
			throw CppSQLite3Exception(nRet,DONT_DELETE_MSG);
		}
	}
}


void CppSQLite3Query::checkVM()
{
	if (mpVM == 0)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,"Null Virtual Machine pointer",DONT_DELETE_MSG);
	}
}


////////////////////////////////////////////////////////////////////////////////

CppSQLite3Table::CppSQLite3Table()
{
	mpaszResults = 0;
	mnRows = 0;
	mnCols = 0;
	mnCurrentRow = 0;
}


CppSQLite3Table::CppSQLite3Table(const CppSQLite3Table& rTable)
{
	mpaszResults = rTable.mpaszResults;
	// Only one object can own the results
	const_cast<CppSQLite3Table&>(rTable).mpaszResults = 0;
	mnRows = rTable.mnRows;
	mnCols = rTable.mnCols;
	mnCurrentRow = rTable.mnCurrentRow;
}


CppSQLite3Table::CppSQLite3Table(char** paszResults,int nCols)
{
	mpaszResults = paszResults;
	mnRows = nRows;
	mnCols = nCols;
	mnCurrentRow = 0;
}


CppSQLite3Table::~CppSQLite3Table()
{
	try
	{
		finalize();
	}
	catch (...)
	{
	}
}


CppSQLite3Table& CppSQLite3Table::operator=(const CppSQLite3Table& rTable)
{
	try
	{
		finalize();
	}
	catch (...)
	{
	}
	mpaszResults = rTable.mpaszResults;
	// Only one object can own the results
	const_cast<CppSQLite3Table&>(rTable).mpaszResults = 0;
	mnRows = rTable.mnRows;
	mnCols = rTable.mnCols;
	mnCurrentRow = rTable.mnCurrentRow;
	return *this;
}


void CppSQLite3Table::finalize()
{
	if (mpaszResults)
	{
		sqlite3_free_table(mpaszResults);
		mpaszResults = 0;
	}
}


int CppSQLite3Table::numFields()
{
	checkResults();
	return mnCols;
}


int CppSQLite3Table::numRows()
{
	checkResults();
	return mnRows;
}


const char* CppSQLite3Table::fieldValue(int nField)
{
	checkResults();

	if (nField < 0 || nField > mnCols-1)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,DONT_DELETE_MSG);
	}

	int nIndex = (mnCurrentRow*mnCols) + mnCols + nField;
	return mpaszResults[nIndex];
}


const char* CppSQLite3Table::fieldValue(const char* szField)
{
	checkResults();

	if (szField)
	{
		for (int nField = 0; nField < mnCols; nField++)
		{
			if (strcmp(szField,mpaszResults[nField]) == 0)
			{
				int nIndex = (mnCurrentRow*mnCols) + mnCols + nField;
				return mpaszResults[nIndex];
			}
		}
	}

	throw CppSQLite3Exception(CPPSQLITE_ERROR,DONT_DELETE_MSG);
}


int CppSQLite3Table::getIntField(int nField,int nNullValue/*=0*/)
{
	if (fieldIsNull(nField))
	{
		return nNullValue;
	}
	else
	{
		return atoi(fieldValue(nField));
	}
}


int CppSQLite3Table::getIntField(const char* szField,int nNullValue/*=0*/)
{
	if (fieldIsNull(szField))
	{
		return nNullValue;
	}
	else
	{
		return atoi(fieldValue(szField));
	}
}


double CppSQLite3Table::getFloatField(int nField,double fNullValue/*=0.0*/)
{
	if (fieldIsNull(nField))
	{
		return fNullValue;
	}
	else
	{
		return atof(fieldValue(nField));
	}
}


double CppSQLite3Table::getFloatField(const char* szField,double fNullValue/*=0.0*/)
{
	if (fieldIsNull(szField))
	{
		return fNullValue;
	}
	else
	{
		return atof(fieldValue(szField));
	}
}


const char* CppSQLite3Table::getStringField(int nField,const char* szNullValue/*=""*/)
{
	if (fieldIsNull(nField))
	{
		return szNullValue;
	}
	else
	{
		return fieldValue(nField);
	}
}


const char* CppSQLite3Table::getStringField(const char* szField,const char* szNullValue/*=""*/)
{
	if (fieldIsNull(szField))
	{
		return szNullValue;
	}
	else
	{
		return fieldValue(szField);
	}
}


bool CppSQLite3Table::fieldIsNull(int nField)
{
	checkResults();
	return (fieldValue(nField) == 0);
}


bool CppSQLite3Table::fieldIsNull(const char* szField)
{
	checkResults();
	return (fieldValue(szField) == 0);
}


const char* CppSQLite3Table::fieldName(int nCol)
{
	checkResults();

	if (nCol < 0 || nCol > mnCols-1)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,DONT_DELETE_MSG);
	}

	return mpaszResults[nCol];
}


void CppSQLite3Table::setRow(int nRow)
{
	checkResults();

	if (nRow < 0 || nRow > mnRows-1)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,"Invalid row index requested",DONT_DELETE_MSG);
	}

	mnCurrentRow = nRow;
}


void CppSQLite3Table::checkResults()
{
	if (mpaszResults == 0)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,"Null Results pointer",DONT_DELETE_MSG);
	}
}


////////////////////////////////////////////////////////////////////////////////

CppSQLite3Statement::CppSQLite3Statement()
{
	mpDB = 0;
	mpVM = 0;
}


CppSQLite3Statement::CppSQLite3Statement(const CppSQLite3Statement& rStatement)
{
	mpDB = rStatement.mpDB;
	mpVM = rStatement.mpVM;
	// Only one object can own VM
	const_cast<CppSQLite3Statement&>(rStatement).mpVM = 0;
}


CppSQLite3Statement::CppSQLite3Statement(sqlite3* pDB,sqlite3_stmt* pVM)
{
	mpDB = pDB;
	mpVM = pVM;
}


CppSQLite3Statement::~CppSQLite3Statement()
{
	try
	{
		finalize();
	}
	catch (...)
	{
	}
}


CppSQLite3Statement& CppSQLite3Statement::operator=(const CppSQLite3Statement& rStatement)
{
	mpDB = rStatement.mpDB;
	mpVM = rStatement.mpVM;
	// Only one object can own VM
	const_cast<CppSQLite3Statement&>(rStatement).mpVM = 0;
	return *this;
}


int CppSQLite3Statement::execDML()
{
	checkDB();
	checkVM();

	const char* szError=0;

	int nRet = sqlite3_step(mpVM);

	if (nRet == SQLITE_DONE)
	{
		int nRowsChanged = sqlite3_changes(mpDB);

		nRet = sqlite3_reset(mpVM);

		if (nRet != SQLITE_OK)
		{
			szError = sqlite3_errmsg(mpDB);
			throw CppSQLite3Exception(nRet,DONT_DELETE_MSG);
		}

		return nRowsChanged;
	}
	else
	{
		nRet = sqlite3_reset(mpVM);
		szError = sqlite3_errmsg(mpDB);
		throw CppSQLite3Exception(nRet,DONT_DELETE_MSG);
	}
}


CppSQLite3Query CppSQLite3Statement::execQuery()
{
	checkDB();
	checkVM();

	int nRet = sqlite3_step(mpVM);

	if (nRet == SQLITE_DONE)
	{
		// no rows
		return CppSQLite3Query(mpDB,mpVM,true/*eof*/,false);
	}
	else if (nRet == SQLITE_ROW)
	{
		// at least 1 row
		return CppSQLite3Query(mpDB,false/*eof*/,false);
	}
	else
	{
		nRet = sqlite3_reset(mpVM);
		const char* szError = sqlite3_errmsg(mpDB);
		throw CppSQLite3Exception(nRet,DONT_DELETE_MSG);
	}
}


void CppSQLite3Statement::bind(int nParam,const char* szValue)
{
	checkVM();
	int nRes = sqlite3_bind_text(mpVM,nParam,szValue,-1,SQLITE_TRANSIENT);

	if (nRes != SQLITE_OK)
	{
		throw CppSQLite3Exception(nRes,"Error binding string param",const int nValue)
{
	checkVM();
	int nRes = sqlite3_bind_int(mpVM,nValue);

	if (nRes != SQLITE_OK)
	{
		throw CppSQLite3Exception(nRes,"Error binding int param",const double dValue)
{
	checkVM();
	int nRes = sqlite3_bind_double(mpVM,dValue);

	if (nRes != SQLITE_OK)
	{
		throw CppSQLite3Exception(nRes,"Error binding double param",int nLen)
{
	checkVM();
	int nRes = sqlite3_bind_blob(mpVM,(const void*)blobValue,nLen,"Error binding blob param",DONT_DELETE_MSG);
	}
}

	
void CppSQLite3Statement::bindNull(int nParam)
{
	checkVM();
	int nRes = sqlite3_bind_null(mpVM,nParam);

	if (nRes != SQLITE_OK)
	{
		throw CppSQLite3Exception(nRes,"Error binding NULL param",DONT_DELETE_MSG);
	}
}


void CppSQLite3Statement::reset()
{
	if (mpVM)
	{
		int nRet = sqlite3_reset(mpVM);

		if (nRet != SQLITE_OK)
		{
			const char* szError = sqlite3_errmsg(mpDB);
			throw CppSQLite3Exception(nRet,DONT_DELETE_MSG);
		}
	}
}


void CppSQLite3Statement::finalize()
{
	if (mpVM)
	{
		int nRet = sqlite3_finalize(mpVM);
		mpVM = 0;

		if (nRet != SQLITE_OK)
		{
			const char* szError = sqlite3_errmsg(mpDB);
			throw CppSQLite3Exception(nRet,DONT_DELETE_MSG);
		}
	}
}


void CppSQLite3Statement::checkDB()
{
	if (mpDB == 0)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,"Database not open",DONT_DELETE_MSG);
	}
}


void CppSQLite3Statement::checkVM()
{
	if (mpVM == 0)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,DONT_DELETE_MSG);
	}
}


////////////////////////////////////////////////////////////////////////////////

CppSQLite3DB::CppSQLite3DB()
{
	mpDB = 0;
	mnBusyTimeoutMs = 60000; // 60 seconds
}


CppSQLite3DB::CppSQLite3DB(const CppSQLite3DB& db)
{
	mpDB = db.mpDB;
	mnBusyTimeoutMs = 60000; // 60 seconds
}


CppSQLite3DB::~CppSQLite3DB()
{
	close();
}


CppSQLite3DB& CppSQLite3DB::operator=(const CppSQLite3DB& db)
{
	mpDB = db.mpDB;
	mnBusyTimeoutMs = 60000; // 60 seconds
	return *this;
}


void CppSQLite3DB::open(const char* szFile)
{
	int nRet = sqlite3_open(szFile,&mpDB);

	if (nRet != SQLITE_OK)
	{
		const char* szError = sqlite3_errmsg(mpDB);
		throw CppSQLite3Exception(nRet,DONT_DELETE_MSG);
	}

	setBusyTimeout(mnBusyTimeoutMs);
}


void CppSQLite3DB::close()
{
	if (mpDB)
	{
		sqlite3_close(mpDB);
		mpDB = 0;
	}
}


CppSQLite3Statement CppSQLite3DB::compileStatement(const char* szSQL)
{
	checkDB();

	sqlite3_stmt* pVM = compile(szSQL);
	return CppSQLite3Statement(mpDB,pVM);
}


bool CppSQLite3DB::tableExists(const char* szTable)
{
	char szSQL[128];
	sprintf(szSQL,"select count(*) from sqlite_master where type='table' and name='%s'",szTable);
	int nRet = execScalar(szSQL);
	return (nRet > 0);
}


int CppSQLite3DB::execDML(const char* szSQL)
{
	checkDB();

	char* szError=0;

	int nRet = sqlite3_exec(mpDB,szSQL,&szError);

	if (nRet == SQLITE_OK)
	{
		return sqlite3_changes(mpDB);
	}
	else
	{
		throw CppSQLite3Exception(nRet,szError);
	}
}


CppSQLite3Query CppSQLite3DB::execQuery(const char* szSQL)
{
	checkDB();

	sqlite3_stmt* pVM = compile(szSQL);

	int nRet = sqlite3_step(pVM);

	if (nRet == SQLITE_DONE)
	{
		// no rows
		return CppSQLite3Query(mpDB,pVM,true/*eof*/);
	}
	else if (nRet == SQLITE_ROW)
	{
		// at least 1 row
		return CppSQLite3Query(mpDB,false/*eof*/);
	}
	else
	{
		nRet = sqlite3_finalize(pVM);
		const char* szError= sqlite3_errmsg(mpDB);
		throw CppSQLite3Exception(nRet,DONT_DELETE_MSG);
	}
}


int CppSQLite3DB::execScalar(const char* szSQL)
{
	CppSQLite3Query q = execQuery(szSQL);

	if (q.eof() || q.numFields() < 1)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,"Invalid scalar query",DONT_DELETE_MSG);
	}

	return atoi(q.fieldValue(0));
}


CppSQLite3Table CppSQLite3DB::getTable(const char* szSQL)
{
	checkDB();

	char* szError=0;
	char** paszResults=0;
	int nRet;
	int nRows(0);
	int nCols(0);

	nRet = sqlite3_get_table(mpDB,&paszResults,&nRows,&nCols,&szError);

	if (nRet == SQLITE_OK)
	{
		return CppSQLite3Table(paszResults,nRows,nCols);
	}
	else
	{
		throw CppSQLite3Exception(nRet,szError);
	}
}


sqlite_int64 CppSQLite3DB::lastRowId()
{
	return sqlite3_last_insert_rowid(mpDB);
}


void CppSQLite3DB::setBusyTimeout(int nMillisecs)
{
	mnBusyTimeoutMs = nMillisecs;
	sqlite3_busy_timeout(mpDB,mnBusyTimeoutMs);
}


void CppSQLite3DB::checkDB()
{
	if (!mpDB)
	{
		throw CppSQLite3Exception(CPPSQLITE_ERROR,DONT_DELETE_MSG);
	}
}


sqlite3_stmt* CppSQLite3DB::compile(const char* szSQL)
{
	checkDB();

	char* szError=0;
	const char* szTail=0;
	sqlite3_stmt* pVM;

	int nRet = sqlite3_prepare(mpDB,&pVM,&szTail);

	if (nRet != SQLITE_OK)
	{
		throw CppSQLite3Exception(nRet,szError);
	}

	return pVM;
}


////////////////////////////////////////////////////////////////////////////////
// SQLite encode.c reproduced here,containing implementation notes and source
// for sqlite3_encode_binary() and sqlite3_decode_binary() 
////////////////////////////////////////////////////////////////////////////////

/*
** 2002 April 25
**
** The author disclaims copyright to this source code.  In place of
** a legal notice,here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely,never taking more than you give.
**
*************************************************************************
** This file contains helper routines used to translate binary data into
** a null-terminated string (suitable for use in SQLite) and back again.
** These are convenience routines for use by people who want to store binary
** data in an SQLite database.  The code in this file is not used by any other
** part of the SQLite library.
**
** $Id: encode.c,v 1.10 2004/01/14 21:59:23 drh Exp $
*/

/*
** How This Encoder Works
**
** The output is allowed to contain any character except 0x27 (') and
** 0x00.  This is accomplished by using an escape character to encode
** 0x27 and 0x00 as a two-byte sequence.  The escape character is always
** 0x01.  An 0x00 is encoded as the two byte sequence 0x01 0x01.  The
** 0x27 character is encoded as the two byte sequence 0x01 0x03.  Finally,** the escape character itself is encoded as the two-character sequence
** 0x01 0x02.
**
** To summarize,the encoder works by using an escape sequences as follows:
**
**       0x00  ->  0x01 0x01
**       0x01  ->  0x01 0x02
**       0x27  ->  0x01 0x03
**
** If that were all the encoder did,it would work,but in certain cases
** it could double the size of the encoded string.  For example,to
** encode a string of 100 0x27 characters would require 100 instances of
** the 0x01 0x03 escape sequence resulting in a 200-character output.
** We would prefer to keep the size of the encoded string smaller than
** this.
**
** To minimize the encoding size,we first add a fixed offset value to each 
** byte in the sequence.  The addition is modulo 256.  (That is to say,if
** the sum of the original character value and the offset exceeds 256,then
** the higher order bits are truncated.)  The offset is chosen to minimize
** the number of characters in the string that need to be escaped.  For
** example,in the case above where the string was composed of 100 0x27
** characters,the offset might be 0x01.  Each of the 0x27 characters would
** then be converted into an 0x28 character which would not need to be
** escaped at all and so the 100 character input string would be converted
** into just 100 characters of output.  Actually 101 characters of output - 
** we have to record the offset used as the first byte in the sequence so
** that the string can be decoded.  Since the offset value is stored as
** part of the output string and the output string is not allowed to contain
** characters 0x00 or 0x27,the offset cannot be 0x00 or 0x27.
**
** Here,then,are the encoding steps:
**
**     (1)   Choose an offset value and make it the first character of
**           output.
**
**     (2)   Copy each input character into the output buffer,one by
**           one,adding the offset value as you copy.
**
**     (3)   If the value of an input character plus offset is 0x00,replace
**           that one character by the two-character sequence 0x01 0x01.
**           If the sum is 0x01,replace it with 0x01 0x02.  If the sum
**           is 0x27,replace it with 0x01 0x03.
**
**     (4)   Put a 0x00 terminator at the end of the output.
**
** Decoding is obvious:
**
**     (5)   Copy encoded characters except the first into the decode 
**           buffer.  Set the first encoded character aside for use as
**           the offset in step 7 below.
**
**     (6)   Convert each 0x01 0x01 sequence into a single character 0x00.
**           Convert 0x01 0x02 into 0x01.  Convert 0x01 0x03 into 0x27.
**
**     (7)   Subtract the offset value that was the first character of
**           the encoded buffer from all characters in the output buffer.
**
** The only tricky part is step (1) - how to compute an offset value to
** minimize the size of the output buffer.  This is accomplished by testing
** all offset values and picking the one that results in the fewest number
** of escapes.  To do that,we first scan the entire input and count the
** number of occurances of each character value in the input.  Suppose
** the number of 0x00 characters is N(0),the number of occurances of 0x01
** is N(1),and so forth up to the number of occurances of 0xff is N(255).
** An offset of 0 is not allowed so we don't have to test it.  The number
** of escapes required for an offset of 1 is N(1)+N(2)+N(40).  The number
** of escapes required for an offset of 2 is N(2)+N(3)+N(41).  And so forth.
** In this way we find the offset that gives the minimum number of escapes,** and thus minimizes the length of the output string.
*/

/*
** Encode a binary buffer "in" of size n bytes so that it contains
** no instances of characters '\'' or '\000'.  The output is 
** null-terminated and can be used as a string value in an INSERT
** or UPDATE statement.  Use sqlite3_decode_binary() to convert the
** string back into its original binary.
**
** The result is written into a preallocated output buffer "out".
** "out" must be able to hold at least 2 +(257*n)/254 bytes.
** In other words,the output will be expanded by as much as 3
** bytes for every 254 bytes of input plus 2 bytes of fixed overhead.
** (This is approximately 2 + 1.0118*n or about a 1.2% size increase.)
**
** The return value is the number of characters in the encoded
** string,excluding the "\000" terminator.
*/
int sqlite3_encode_binary(const unsigned char *in,unsigned char *out){
  int i,j,e,m;
  int cnt[256];
  if( n<=0 ){
    out[0] = 'x';
    out[1] = 0;
    return 1;
  }
  memset(cnt,sizeof(cnt));
  for(i=n-1; i>=0; i--){ cnt[in[i]]++; }
  m = n;
  for(i=1; i<256; i++){
    int sum;
    if( i=='\'' ) continue;
    sum = cnt[i] + cnt[(i+1)&0xff] + cnt[(i+'\'')&0xff];
    if( sum<m ){
      m = sum;
      e = i;
      if( m==0 ) break;
    }
  }
  out[0] = e;
  j = 1;
  for(i=0; i<n; i++){
    int c = (in[i] - e)&0xff;
    if( c==0 ){
      out[j++] = 1;
      out[j++] = 1;
    }else if( c==1 ){
      out[j++] = 1;
      out[j++] = 2;
    }else if( c=='\'' ){
      out[j++] = 1;
      out[j++] = 3;
    }else{
      out[j++] = c;
    }
  }
  out[j] = 0;
  return j;
}

/*
** Decode the string "in" into binary data and write it into "out".
** This routine reverses the encoding created by sqlite3_encode_binary().
** The output will always be a few bytes less than the input.  The number
** of bytes of output is returned.  If the input is not a well-formed
** encoding,-1 is returned.
**
** The "in" and "out" parameters may point to the same buffer in order
** to decode a string in place.
*/
int sqlite3_decode_binary(const unsigned char *in,c,e;
  e = *(in++);
  i = 0;
  while( (c = *(in++))!=0 ){
    if( c==1 ){
      c = *(in++);
      if( c==1 ){
        c = 0;
      }else if( c==2 ){
        c = 1;
      }else if( c==3 ){
        c = '\'';
      }else{
        return -1;
      }
    }
    out[i++] = (c + e)&0xff;
  }
  return i;
}
这里还有一个外国哥们写的一个SQLite C++类http://www.adp-gmbh.ch/sqlite/wrapper.html,具体哪个好,还没比较过,试试吧

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SQLite,是一款轻型的数据库,是遵守ACID的关系型数据库管理系统,它包含在一个相对小的C库中。它是D.RichardHipp建立的公有领域项目。它的设计目标是嵌入式的,而且已经在很多嵌入式产品中使用了它,它占用资源非常的低,在嵌入式设备中,可能只需要几百K的内存就够了。它能够支持Windows/Linux/Unix等等主流的操作系统,同时能够跟很多程序语言相结合,比如 Tcl、C#、PHP、Java等,还有ODBC接口,同样比起Mysql、PostgreSQL这两款开源的世界著名数据库...
Qt设计较为美观好看的登录注册界面(包含SQLite数据库以及TCP通信的应用)
SQLite是用C语言开发的跨平台小型数据库,可嵌入其他开发语言,也可在单机执行。SPL是用Java开发的跨平台的数据计算语言,可嵌入Java,可在单机执行,可以数据计算服务的形式被远程调用。两者的代码都是解释执行的。...
新建库.openDATA_BASE;新建表createtableLIST_NAME(DATA);语法:NAME关键字...<用逗号分割>删除表droptableNAME;查看表.schema查看表信息新建数据insertintoLIST_NAMEvalues();语法:CLASS,PARAMETER...,CLASS是类别,PARAMETER是参数<用逗号分割新建的
importsqlite3classDemo01:def__init__(self):self.conn=sqlite3.connect("sql_demo_001.db")self.cursor1=self.conn.cursor()self.cursor1.execute("select*fromtable_001wherename=?andid=?",('ssss&#0
 在客户端配置文件<configuration>节点下,添加:<connectionStrings>      <add name="localdb" connectionString="Data Source=config/local.db;Version=3;UseUTF16Encoding=True;" providerName="System.Data.SQLite.SQLiteFactory"/&g
提到锁就不得不说到死锁的问题,而SQLite也可能出现死锁。下面举个例子:连接1:BEGIN(UNLOCKED)连接1:SELECT...(SHARED)连接1:INSERT...(RESERVED)连接2:BEGIN(UNLOCKED)连接2:SELECT...(SHARED)连接1:COMMIT(PENDING,尝试获取EXCLUSIVE锁,但还有SHARED锁未释放,返回SQLITE_BUSY)连接2:INSERT...
SQLite是一种嵌入式数据库,它的数据库就是一个文件。由于SQLite本身是C写的,而且体积很小,所以,经常被集成到各种应用程序中,甚至在iOS和Android的App中都可以集成。Python就内置了SQLite3,所以,在Python中使用SQLite,不需要安装任何东西,直接使用。在使用SQLite前,我们先要搞清楚几个概念:表
设计思想————首先要确定有几个页面、和每个页面的大致布局由于是入门,我也是学习了不是很长的时间,所以项目比较low。。。。第一个页面,也就是打开APP的首页面:今天这个博客,先实现添加功能!:首先对主界面进行布局:其中activity_main.xml的代码为<?xmlversion="1.0"encoding="