C++使用Sqlite3,使用CppSQLite3的封装
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2023-11-01 19:49:16
使用CppSQLite3后操作Sqlite3更加方便
CppSQLite3.h
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使用CppSQLite3后操作Sqlite3更加方便
CppSQLite3.h
//////////////////////////////////////////////////////////////////////////////// // CppSQLite3 - A C++ wrapper around the SQLite3 embedded database library. // // Copyright (c) 2004..2007 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() // // V3.2 01/07/2005 -Fixed execScalar to handle a NULL result // 12/07/2007 -Added CppSQLiteDB::IsAutoCommitOn() // -Added int64 functions to CppSQLite3Query // -Added Name based parameter binding to CppSQLite3Statement. //////////////////////////////////////////////////////////////////////////////// #ifndef _CppSQLite3_H_ #define _CppSQLite3_H_ #include "sqlite3.h" #include #include #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); sqlite_int64 getInt64Field(int nField, sqlite_int64 nNullValue=0); sqlite_int64 getInt64Field(const char* szField, sqlite_int64 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, 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=""); 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); int bindParameterIndex(const char* szParam); void bind(const char* szParam, const char* szValue); void bind(const char* szParam, const int nValue); void bind(const char* szParam, const double dwValue); void bind(const char* szParam, const unsigned char* blobValue, int nLen); void bindNull(const char* szParam); 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, int nNullValue=0); 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; } static const char* SQLiteHeaderVersion() { return SQLITE_VERSION; } static const char* SQLiteLibraryVersion() { return sqlite3_libversion(); } static int SQLiteLibraryVersionNumber() { return sqlite3_libversion_number(); } bool IsAutoCommitOn(); private: CppSQLite3DB(const CppSQLite3DB& db); CppSQLite3DB& operator=(const CppSQLite3DB& db); sqlite3_stmt* compile(const char* szSQL); void checkDB(); sqlite3* mpDB; int mnBusyTimeoutMs; }; #endif
CppSQLite3.cpp
//////////////////////////////////////////////////////////////////////////////// // CppSQLite3 - A C++ wrapper around the SQLite3 embedded database library. // // Copyright (c) 2004..2007 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() // // V3.2 01/07/2005 -Fixed execScalar to handle a NULL result // 12/07/2007 -Added int64 functions to CppSQLite3Query // -Throw exception from CppSQLite3DB::close() if error // -Trap above exception in CppSQLite3DB::~CppSQLite3DB() // -Fix to CppSQLite3DB::compile() as provided by Dave Rollins. // -sqlite3_prepare replaced with sqlite3_prepare_v2 // -Added Name based parameter binding to CppSQLite3Statement. //////////////////////////////////////////////////////////////////////////////// #include "CppSQLite3.h" #include // 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, char* szErrMess, 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, pBuf, 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, "Cannot allocate memory", 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(rQuery).mpVM = 0; mbEof = rQuery.mbEof; mnCols = rQuery.mnCols; mbOwnVM = rQuery.mbOwnVM; } CppSQLite3Query::CppSQLite3Query(sqlite3* pDB, sqlite3_stmt* pVM, bool bEof, 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(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); } sqlite_int64 CppSQLite3Query::getInt64Field(int nField, sqlite_int64 nNullValue/*=0*/) { if (fieldDataType(nField) == SQLITE_NULL) { return nNullValue; } else { return sqlite3_column_int64(mpVM, nField); } } sqlite_int64 CppSQLite3Query::getInt64Field(const char* szField, sqlite_int64 nNullValue/*=0*/) { int nField = fieldIndex(szField); return getInt64Field(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, "Invalid field index requested", 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, "Invalid field index requested", 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, "Invalid field index requested", 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, "Invalid field index requested", 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, (char*)szError, 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(rTable).mpaszResults = 0; mnRows = rTable.mnRows; mnCols = rTable.mnCols; mnCurrentRow = rTable.mnCurrentRow; } CppSQLite3Table::CppSQLite3Table(char** paszResults, int nRows, 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(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, "Invalid field index requested", 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, "Invalid field name requested", 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, "Invalid field index requested", 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(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(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, (char*)szError, DONT_DELETE_MSG); } return nRowsChanged; } else { nRet = sqlite3_reset(mpVM); szError = sqlite3_errmsg(mpDB); throw CppSQLite3Exception(nRet, (char*)szError, 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, mpVM, false/*eof*/, false); } else { nRet = sqlite3_reset(mpVM); const char* szError = sqlite3_errmsg(mpDB); throw CppSQLite3Exception(nRet, (char*)szError, 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", DONT_DELETE_MSG); } } void CppSQLite3Statement::bind(int nParam, const int nValue) { checkVM(); int nRes = sqlite3_bind_int(mpVM, nParam, nValue); if (nRes != SQLITE_OK) { throw CppSQLite3Exception(nRes, "Error binding int param", DONT_DELETE_MSG); } } void CppSQLite3Statement::bind(int nParam, const double dValue) { checkVM(); int nRes = sqlite3_bind_double(mpVM, nParam, dValue); if (nRes != SQLITE_OK) { throw CppSQLite3Exception(nRes, "Error binding double param", DONT_DELETE_MSG); } } void CppSQLite3Statement::bind(int nParam, const unsigned char* blobValue, int nLen) { checkVM(); int nRes = sqlite3_bind_blob(mpVM, nParam, (const void*)blobValue, nLen, SQLITE_TRANSIENT); if (nRes != SQLITE_OK) { throw CppSQLite3Exception(nRes, "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); } } int CppSQLite3Statement::bindParameterIndex(const char* szParam) { checkVM(); int nParam = sqlite3_bind_parameter_index(mpVM, szParam); int nn = sqlite3_bind_parameter_count(mpVM); const char* sz1 = sqlite3_bind_parameter_name(mpVM, 1); const char* sz2 = sqlite3_bind_parameter_name(mpVM, 2); if (!nParam) { char buf[128]; sprintf(buf, "Parameter '%s' is not valid for this statement", szParam); throw CppSQLite3Exception(CPPSQLITE_ERROR, buf, DONT_DELETE_MSG); } return nParam; } void CppSQLite3Statement::bind(const char* szParam, const char* szValue) { int nParam = bindParameterIndex(szParam); bind(nParam, szValue); } void CppSQLite3Statement::bind(const char* szParam, const int nValue) { int nParam = bindParameterIndex(szParam); bind(nParam, nValue); } void CppSQLite3Statement::bind(const char* szParam, const double dwValue) { int nParam = bindParameterIndex(szParam); bind(nParam, dwValue); } void CppSQLite3Statement::bind(const char* szParam, const unsigned char* blobValue, int nLen) { int nParam = bindParameterIndex(szParam); bind(nParam, blobValue, nLen); } void CppSQLite3Statement::bindNull(const char* szParam) { int nParam = bindParameterIndex(szParam); bindNull(nParam); } void CppSQLite3Statement::reset() { if (mpVM) { int nRet = sqlite3_reset(mpVM); if (nRet != SQLITE_OK) { const char* szError = sqlite3_errmsg(mpDB); throw CppSQLite3Exception(nRet, (char*)szError, 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, (char*)szError, 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, "Null Virtual Machine pointer", 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() { try { close(); } catch (...) { } } 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, (char*)szError, DONT_DELETE_MSG); } setBusyTimeout(mnBusyTimeoutMs); } void CppSQLite3DB::close() { if (mpDB) { if (sqlite3_close(mpDB) == SQLITE_OK) { mpDB = 0; } else { throw CppSQLite3Exception(CPPSQLITE_ERROR, "Unable to close database", DONT_DELETE_MSG); } } } CppSQLite3Statement CppSQLite3DB::compileStatement(const char* szSQL) { checkDB(); sqlite3_stmt* pVM = compile(szSQL); return CppSQLite3Statement(mpDB, pVM); } bool CppSQLite3DB::tableExists(const char* szTable) { char szSQL[256]; 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, 0, 0, &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, pVM, false/*eof*/); } else { nRet = sqlite3_finalize(pVM); const char* szError= sqlite3_errmsg(mpDB); throw CppSQLite3Exception(nRet, (char*)szError, DONT_DELETE_MSG); } } int CppSQLite3DB::execScalar(const char* szSQL, int nNullValue/*=0*/) { CppSQLite3Query q = execQuery(szSQL); if (q.eof() || q.numFields() < 1) { throw CppSQLite3Exception(CPPSQLITE_ERROR, "Invalid scalar query", DONT_DELETE_MSG); } return q.getIntField(0, nNullValue); } 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, szSQL, &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, "Database not open", DONT_DELETE_MSG); } } sqlite3_stmt* CppSQLite3DB::compile(const char* szSQL) { checkDB(); const char* szTail=0; sqlite3_stmt* pVM; int nRet = sqlite3_prepare_v2(mpDB, szSQL, -1, &pVM, &szTail); if (nRet != SQLITE_OK) { const char* szError = sqlite3_errmsg(mpDB); throw CppSQLite3Exception(nRet, (char*)szError, DONT_DELETE_MSG); } return pVM; } bool CppSQLite3DB::IsAutoCommitOn() { checkDB(); return sqlite3_get_autocommit(mpDB) ? true : false; } //////////////////////////////////////////////////////////////////////////////// // 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, int n, unsigned char *out){ int i, j, e, m; int cnt[256]; if( n<=0 ){ out[0] = 'x'; out[1] = 0; return 1; } memset(cnt, 0, 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(="" )="" break;="" }="" out[0]="e;" j="1;" for(i="0;" i<n;="" i++){="" int="" c="(in[i]" -="" e)&0xff;="" out[j++]="1;" }else="" }else{="" out[j]="0;" return="" j;="" *="" **="" decode="" the="" string="" "in"="" into="" binary="" data="" and="" write="" it="" "out".="" this="" routine="" reverses="" encoding="" created="" by="" sqlite3_encode_binary().="" output="" will="" always="" be="" a="" few="" bytes="" less="" than="" input.="" number="" of="" is="" returned.="" if="" input="" not="" well-formed="" encoding,="" -1="" "out"="" parameters="" may="" point="" to="" same="" buffer="" in="" order="" place.="" sqlite3_decode_binary(const="" unsigned="" char="" *in,="" *out){="" i,="" c,="" e;="" i="0;" while(="" (c="*(in++))!=0" ';="" -1;="" out[i++]="(c" +="" i;=""
使用方法
#include #include "CppSQLite3.h" #include using namespace std; const char * gszFile = "e:\\sqlite3\\test.db"; //测试Sqlite3的使用 void main1() { cout << "hello sqlite3" << endl; try { int i, fld; time_t tmStart, tmEnd; CppSQLite3DB db; char *sql; cout << "SQLite Header Version: " << CppSQLite3DB::SQLiteHeaderVersion() << endl; cout << "SQLite Library Version: " << CppSQLite3DB::SQLiteLibraryVersion() << endl; cout << "SQLite Library Version Number: " << CppSQLite3DB::SQLiteLibraryVersionNumber() << endl; //remove(gszFile); db.open(gszFile); //插入数据 cout << endl << "emp table exists=" << (db.tableExists("person") ? "TRUE" : "FALSE") << endl; // Create SQL statement sql = "CREATE TABLE person(" \ "id INT PRIMARY KEY NOT NULL," \ "name TEXT NOT NULL," \ "age INT NOT NULL," \ "address CHAR(50)," \ "salary REAL );"; //db.execDML(sql); //cout << endl << "emp table exists=" << (db.tableExists("person") ? "TRUE" : "FALSE") << endl; //cout << endl << "DML tests" << endl; sql = "insert into person values (1, 'David Beckham',34,'china person',3455.78);"\ "insert into person values (2, 'changshuhang',33,'china person1',3455.34);"\ "insert into person values (3, 'houyuzhu',37,'china person2',34534);"\ "insert into person values (4, 'chengye',356,'china person3',45.78);"\ "insert into person values (5, 'dujianfei',38,'china person4',3655.78);"; int nRows = db.execDML(sql); cout << nRows << " rows inserted" << endl; //update /* sql = "update person set name = 'xi*' where id = 5 ;"\ "update person set name = 'hujingtao' where address = 'china person2' ;"; int nRows = db.execDML(sql); cout << nRows << " rows updated" << endl; */ //delete /* sql = "delete from person where id = 5 ;"\ "delete from person where address = 'china person2' ;"; int nRows = db.execDML(sql); cout << nRows << " rows updated" << endl; */ /* // Query data and also show results of inserts into auto-increment field cout << endl << "Select statement test" << endl; CppSQLite3Query q = db.execQuery("select * from person order by id;"); for (fld = 0; fld < q.numFields(); fld++) { cout << q.fieldName(fld) << "(" << q.fieldDeclType(fld) << ")|"; } cout << endl; while (!q.eof()) { cout << q.fieldValue(0) << "|"; cout << q.fieldValue(1) << "|"; cout << q.fieldValue(2) << "|"; cout << q.fieldValue(3) << endl; q.nextRow(); } */ /* // Fetch table at once, and also show how to use CppSQLiteTable::setRow() method cout << endl << "getTable() test" << endl; CppSQLite3Table t = db.getTable("select * from person order by id;"); for (fld = 0; fld < t.numFields(); fld++) { cout << t.fieldName(fld) << "|"; } cout << endl; for (int row = 0; row < t.numRows(); row++) { t.setRow(row); for (int fld = 0; fld < t.numFields(); fld++) { if (!t.fieldIsNull(fld)) cout << t.fieldValue(fld) << "|"; else cout << "NULL" << "|"; } cout << endl; } */ } catch (CppSQLite3Exception& e) { cerr << e.errorCode() << ":" << e.errorMessage() << endl; } //////////////////////////////////////////////////////////////////////////////// // Loop until user enters q or Q //////////////////////////////////////////////////////////////////////////////// char c(' '); while (c != 'q' && c != 'Q') { cout << "Press q then enter to quit: "; cin >> c; } }
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