--- sql/odbc/parser3odbc.C 2008/06/27 14:02:24 1.29 +++ sql/odbc/parser3odbc.C 2008/07/08 09:21:08 1.35 @@ -5,7 +5,7 @@ Author: Alexandr Petrosian (http://paf.design.ru) */ -static const char *RCSId="$Id: parser3odbc.C,v 1.29 2008/06/27 14:02:24 misha Exp $"; +static const char *RCSId="$Id: parser3odbc.C,v 1.35 2008/07/08 09:21:08 misha Exp $"; #ifndef _MSC_VER # error compile ISAPI module with MSVC [no urge for now to make it autoconf-ed (PAF)] @@ -70,13 +70,29 @@ static void toupper_str(char *out, const *out++=(char)toupper(*in++); } +struct modified_statement { + const char* statement; + bool limit; + bool offset; +}; + +// todo: MySQL, SQLite, PgSQL (add LIMIT at the end of statement) +struct SQL { + enum SQLEnum { + Undefined, + MSSQL, + Pervasive, + FireBird + }; +}; + struct Connection { SQL_Driver_services* services; CDatabase* db; const char* client_charset; + SQL::SQLEnum sql_specific; bool autocommit; - bool fast_offset_search; }; /** @@ -96,8 +112,8 @@ public: @param url format: @b DSN=dsn;UID=user;PWD=password? (ODBC connect string) ClientCharset=charset& // transcode with parser - FastOffsetSearch=0& // 0 -- disable (slower) autocommit=1& // 0 -- disable auto commit + FastOffsetSearch=0 WARNING: must be used only to connect, for buffer doesn't live long */ @@ -110,12 +126,14 @@ public: *connection_ref=&connection; connection.services=&services; connection.client_charset=0; - connection.fast_offset_search=false; + connection.sql_specific=SQL::Undefined; connection.autocommit=true; size_t url_length=strlen(url); char *options=lsplit(url, '?'); + // todo: analize connect string and if 'SQL Server' found, modify query and add TOP into SELECTs + while(options){ if(char *key=lsplit(&options, '&')){ if(*key){ @@ -126,9 +144,16 @@ public: } else if(strcasecmp(key, "autocommit")==0){ if(atoi(value)==0) connection.autocommit=false; - } else if(strcmp(key, "FastOffsetSearch")==0){ - if(atoi(value)==1) - connection.fast_offset_search=true; + } else if(strcmp(key, "SQL")==0){ + if(strcasecmp(value, "MSSQL")==0){ + connection.sql_specific=SQL::MSSQL; + } else if(strcasecmp(value, "Pervasive")==0){ + connection.sql_specific=SQL::Pervasive; + } else if(strcasecmp(value, "FireBird")==0){ + connection.sql_specific=SQL::FireBird; + } else { + services._throw("unknown value of SQL option was specified" /*key*/); + } } else services._throw("unknown connect option" /*key*/); } else @@ -140,9 +165,7 @@ public: TRY { connection.db=new CDatabase(); connection.db->OpenEx(url, CDatabase::noOdbcDialog); - - if(!connection.autocommit) - connection.db->BeginTrans(); + connection.db->BeginTrans(); } CATCH_ALL (e) { _throw(services, e); @@ -163,28 +186,24 @@ public: void commit(void *aconnection){ Connection& connection=*static_cast(aconnection); - if(!connection.autocommit){ - TRY - connection.db->CommitTrans(); - connection.db->BeginTrans(); - CATCH_ALL (e) { - _throw(*connection.services, e); - } - END_CATCH_ALL + TRY + connection.db->CommitTrans(); + connection.db->BeginTrans(); + CATCH_ALL (e) { + _throw(*connection.services, e); } + END_CATCH_ALL } void rollback(void *aconnection){ Connection& connection=*static_cast(aconnection); - if(!connection.autocommit){ - TRY - connection.db->Rollback(); - connection.db->BeginTrans(); - CATCH_ALL (e) { - _throw(*connection.services, e); - } - END_CATCH_ALL + TRY + connection.db->Rollback(); + connection.db->BeginTrans(); + CATCH_ALL (e) { + _throw(*connection.services, e); } + END_CATCH_ALL } bool ping(void *connection){ @@ -206,7 +225,7 @@ public: } void query(void *aconnection, - const char *statement, + const char *astatement, size_t placeholders_count, Placeholder* placeholders, unsigned long offset, @@ -220,20 +239,24 @@ public: if(placeholders_count>0) services._throw("bind variables not supported (yet)"); - bool transcode_needed=_transcode_required(connection); + while(isspace((unsigned char)*astatement)) + astatement++; - // transcode query from $request:charset to ?ClientCharset + modified_statement mstatement=_preprocess_statement(connection, astatement, offset, limit); + const char* statement=mstatement.statement; + + const char* client_charset=connection.client_charset; + const char* request_charset=services.request_charset(); + bool transcode_needed=(client_charset && strcmp(client_charset, request_charset)!=0); if(transcode_needed){ + // transcode query from $request:charset to ?ClientCharset size_t length=strlen(statement); services.transcode(statement, length, statement, length, - services.request_charset(), - connection.client_charset); + request_charset, + client_charset); } - while(isspace((unsigned char)*statement)) - statement++; - TRY { // mk:@MSITStore:C:\Program%20Files\Microsoft%20SQL%20Server\80\Tools\Books\adosql.chm::/adoprg02_4g33.htm // or http://msdn.microsoft.com/en-us/library/aa905899(SQL.80).aspx @@ -244,27 +267,17 @@ public: // mk:@MSITStore:C:\Program%20Files\Microsoft%20SQL%20Server\80\Tools\Books\odbcsql.chm::/od_6_035_5dnp.htm // The ODBC CALL escape sequence for calling a procedure is: // {[?=]call procedure_name[([parameter][,[parameter]]...)]} - if(strncasecmp(statement, "SELECT", 6)==0 + if( + strncasecmp(statement, "SELECT", 6)==0 || strncasecmp(statement, "EXEC", 4)==0 || strncasecmp(statement, "call", 4)==0 || strncasecmp(statement, "{", 1)==0 ){ CRecordset rs(db); DWORD options=CRecordset::executeDirect|CRecordset::readOnly; - //CRecordset::skipDeletedRecords - //CRecordset::useMultiRowFetch - //CRecordset::userAllocMultiRowBuffers - //CRecordset::useExtendedFetch -/* - if(connection.fast_offset_search){ - options+=CRecordset::useMultiRowFetch+CRecordset::userAllocMultiRowBuffers; - } else { - options+=CRecordset::skipDeletedRecords; - } -*/ TRY { rs.Open( - (connection.fast_offset_search)?CRecordset::dynamic:CRecordset::forwardOnly, + CRecordset::forwardOnly, statement, options ); @@ -289,6 +302,7 @@ public: column_count=MAX_COLS; SWORD column_types[MAX_COLS]; + bool transcode_column[MAX_COLS]; SQL_Error sql_error; #define CHECK(afailed) if(afailed) services._throw(sql_error) @@ -298,6 +312,24 @@ public: CODBCFieldInfo fieldinfo; rs.GetODBCFieldInfo(i, fieldinfo); column_types[i]=fieldinfo.m_nSQLType; + switch(fieldinfo.m_nSQLType){ + case SQL_NUMERIC: + case SQL_DECIMAL: + case SQL_INTEGER: + case SQL_SMALLINT: + case SQL_FLOAT: + case SQL_REAL: + case SQL_DOUBLE: + case SQL_DATETIME: + case SQL_SMALLDATETIME: + case SQL_BIGINT: + case SQL_TINYINT: + transcode_column[i]=false; + break; + default: + transcode_column[i]=transcode_needed; + break; + } size_t length=fieldinfo.m_strName.GetLength(); char *str=0; if(length){ @@ -308,8 +340,8 @@ public: if(transcode_needed){ services.transcode(str, length, str, length, - connection.client_charset, - services.request_charset()); + client_charset, + request_charset); } } CHECK(handlers.add_column(sql_error, str, length)); @@ -318,16 +350,10 @@ public: CHECK(handlers.before_rows(sql_error)); // skip offset rows - if(offset){ - if(connection.fast_offset_search){ - rs.Move(offset); - } else { - unsigned long row=offset; - while(!rs.IsEOF() && row>0){ - rs.MoveNext(); - row--; - } - } + if(offset && !mstatement.offset){ + unsigned long row=offset; + while(!rs.IsEOF() && row--) + rs.MoveNext(); } unsigned long row=0; @@ -340,7 +366,6 @@ public: char* str; switch(column_types[i]){ //case xBOOL: - //case SQL_INTEGER: // serg@design.ru did that in parser2. test first! //case SQL_DATETIME: << default: handles that more properly (?) case SQL_BINARY: case SQL_VARBINARY: @@ -358,11 +383,12 @@ public: } // transcode cell value from ?ClientCharset to $request:charset - if(transcode_needed && length) + if(length && transcode_column[i]){ services.transcode(str, length, str, length, - connection.client_charset, - services.request_charset()); + client_charset, + request_charset); + } CHECK(handlers.add_row_cell(sql_error, str, length)); } @@ -377,6 +403,9 @@ public: } CATCH_ALL (e) { _throw(services, e); } END_CATCH_ALL + + if(connection.autocommit) + commit(aconnection); } private: @@ -401,7 +430,7 @@ private: ptr=v.m_boolVal?"1":"0"; length=1; break;*/ -/* case DBVT_UCHAR: +/* case DBVT_UCHAR: length=strlen(ptr=v.m_chVal); break; case DBVT_SHORT: @@ -461,6 +490,72 @@ private: } } + modified_statement _preprocess_statement( + Connection& connection, + const char* astatement, + unsigned long offset, + unsigned long limit + ){ + modified_statement result={astatement, false, false}; + + if(limit!=SQL_NO_LIMIT && connection.sql_specific!=SQL::Undefined && strncasecmp(astatement, "select", 6)==0){ + switch(connection.sql_specific){ + case SQL::MSSQL: + case SQL::Pervasive: // uses TOP as well + { + // add ' TOP limit+offset' after 'SELECT' + char* statement_limited=(char *)connection.services->malloc_atomic( + strlen(astatement) + +MAX_NUMBER + +5/* TOP */ + +1/*terminator*/ + ); + + result.limit=true; + if(!limit) + result.offset=true; // mark as we'll did it in query because of no point to skip anything if we need 0 rows + result.statement=statement_limited; + + snprintf(statement_limited, MAX_NUMBER+11, "SELECT TOP %u", (limit)?limit+offset:0/*no point to skip anything if we need 0 rows*/); + + astatement+=6;/*skip 'select'*/ + strcat(statement_limited, astatement); + + //connection.services->_throw(result.statement); + break; + } + case SQL::FireBird: + { + // add ' FIRST (limit) SKIP (offset)' after 'SELECT' + char* statement_limited=(char *)connection.services->malloc_atomic( + strlen(astatement) + +MAX_NUMBER*2 + +9/* FIRST ()*/ + +offset?8:0/* SKIP ()*/ + +1/*terminator*/ + ); + + result.limit=true; + result.offset=true; + result.statement=statement_limited; + + statement_limited+=snprintf(statement_limited, MAX_NUMBER+15, "SELECT FIRST (%u)", limit); + if(offset && limit/*no reasons to skip something if we need 0 rows*/) + statement_limited+=snprintf(statement_limited, MAX_NUMBER+8, " SKIP (%u)", offset); + + astatement+=6;/*skip 'select'*/ + strcat((char*)result.statement, astatement); + + //connection.services->_throw(result.statement); + break; + } + default: + connection.services->_throw("Unknown SQL specifics"); + } + } + return result; + } + void _throw(SQL_Driver_services& services, CException *e){ char szCause[MAX_STRING]; szCause[0]=0; @@ -478,10 +573,6 @@ private: connection.services->_throw(msg); } - bool _transcode_required(Connection& connection){ - return (connection.client_charset && strcmp(connection.client_charset, connection.services->request_charset())!=0); - } - }; extern "C" SQL_Driver *SQL_DRIVER_CREATE() {