query.h

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/***********************************************************************
 Copyright (c) 1998 by Kevin Atkinson, (c) 1999-2001 by MySQL AB, and
 (c) 2004-2011 by Educational Technology Resources, Inc.  Others may
 also hold copyrights on code in this file.  See the CREDITS.txt file
 in the top directory of the distribution for details.

 This file is part of MySQL++.

 MySQL++ is free software; you can redistribute it and/or modify it
 under the terms of the GNU Lesser General Public License as published
 by the Free Software Foundation; either version 2.1 of the License, or
 (at your option) any later version.

 MySQL++ is distributed in the hope that it will be useful, but WITHOUT
 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
 License for more details.

 You should have received a copy of the GNU Lesser General Public
 License along with MySQL++; if not, write to the Free Software
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301
 USA
***********************************************************************/

#if !defined(MYSQLPP_QUERY_H)
#define MYSQLPP_QUERY_H

#include "common.h"

#include "exceptions.h"
#include "noexceptions.h"
#include "qparms.h"
#include "querydef.h"
#include "result.h"
#include "row.h"
#include "sqlstream.h"
#include "stadapter.h"
#include "transaction.h"

#include <deque>
#include <iomanip>
#include <list>
#include <map>
#include <set>
#include <vector>

#ifdef HAVE_EXT_SLIST
#  include <ext/slist>
#else
#  if defined(HAVE_STD_SLIST) || defined(HAVE_GLOBAL_SLIST)
#      include <slist>
#  endif
#endif

namespace mysqlpp {

#if !defined(DOXYGEN_IGNORE)
// Make Doxygen ignore this
class MYSQLPP_EXPORT Connection;
class MYSQLPP_EXPORT Transaction;
#endif


class MYSQLPP_EXPORT Query :
                public std::ostream,
                public OptionalExceptions
{
public:
#if !defined(DOXYGEN_IGNORE)
        // Bring in InsertPolicy template as part of this class's interface,
        // separate only in the sense that it's a self-contained concept.
        #include "insertpolicy.h"
#endif

        Query(Connection* c, bool te = true, const char* qstr = 0);

        Query(const Query& q);

        ulonglong affected_rows();

        size_t escape_string(std::string* ps, const char* original = 0,
                        size_t length = 0) const;

        size_t escape_string(char* escaped, const char* original,
                        size_t length) const;

        int errnum() const;

        const char* error() const;

        std::string info();

        ulonglong insert_id();

        Query& operator=(const Query& rhs);

        operator void*() const;

        bool operator !() const { return !operator void*(); }

        void parse();

        void reset();

        bool result_empty();

        std::string str() { return str(template_defaults); }

        std::string str(const SQLTypeAdapter& arg0)
                        { return str(SQLQueryParms() << arg0); }

        std::string str(SQLQueryParms& p);

        bool exec() { return exec(str(template_defaults)); }

        bool exec(const std::string& str);

        SimpleResult execute(); 

        SimpleResult execute(SQLQueryParms& p);

        SimpleResult execute(const SQLTypeAdapter& str);

        SimpleResult execute(const char* str, size_t len);

        UseQueryResult use();

        UseQueryResult use(SQLQueryParms& p);

        UseQueryResult use(const SQLTypeAdapter& str);

        UseQueryResult use(const char* str, size_t len);

        StoreQueryResult store();

        StoreQueryResult store(SQLQueryParms& p);

        StoreQueryResult store(const SQLTypeAdapter& str);

        StoreQueryResult store(const char* str, size_t len);

        template <typename Function>
        Function for_each(const SQLTypeAdapter& query, Function fn)
        {       
                mysqlpp::UseQueryResult res = use(query);
                if (res) {
                        mysqlpp::NoExceptions ne(res);
                        while (mysqlpp::Row row = res.fetch_row()) {
                                fn(row);
                        }
                }

                return fn;
        }

        template <typename Function>
        Function for_each(Function fn)
        {       
                mysqlpp::UseQueryResult res = use();
                if (res) {
                        mysqlpp::NoExceptions ne(res);
                        while (mysqlpp::Row row = res.fetch_row()) {
                                fn(row);
                        }
                }

                return fn;
        }

        template <class SSQLS, typename Function>
        Function for_each(const SSQLS& ssqls, Function fn)
        {       
                std::string query("select * from `");
                query += ssqls.table();
      query += '`';
                mysqlpp::UseQueryResult res = use(query);
                if (res) {
                        mysqlpp::NoExceptions ne(res);
                        while (mysqlpp::Row row = res.fetch_row()) {
                                fn(row);
                        }
                }

                return fn;
        }

        template <class Sequence, typename Function>
        Function store_if(Sequence& con, const SQLTypeAdapter& query, Function fn)
        {       
                mysqlpp::UseQueryResult res = use(query);
                if (res) {
                        mysqlpp::NoExceptions ne(res);
                        while (mysqlpp::Row row = res.fetch_row()) {
                                if (fn(row)) {
                                        con.push_back(row);
                                }
                        }
                }

                return fn;
        }

        template <class Sequence, class SSQLS, typename Function>
        Function store_if(Sequence& con, const SSQLS& ssqls, Function fn)
        {       
                std::string query("select * from `");
                query += ssqls.table();
      query += '`';
                mysqlpp::UseQueryResult res = use(query);
                if (res) {
                        mysqlpp::NoExceptions ne(res);
                        while (mysqlpp::Row row = res.fetch_row()) {
                                if (fn(row)) {
                                        con.push_back(row);
                                }
                        }
                }

                return fn;
        }

        template <class Sequence, typename Function>
        Function store_if(Sequence& con, Function fn)
        {       
                mysqlpp::UseQueryResult res = use();
                if (res) {
                        mysqlpp::NoExceptions ne(res);
                        while (mysqlpp::Row row = res.fetch_row()) {
                                if (fn(row)) {
                                        con.push_back(row);
                                }
                        }
                }

                return fn;
        }

        StoreQueryResult store_next();

        bool more_results();

        template <class Sequence>
        void storein_sequence(Sequence& con)
        {
                storein_sequence(con, str(template_defaults));
        }

        template <class Sequence>
        void storein_sequence(Sequence& con, const SQLTypeAdapter& s)
        {
                if (UseQueryResult result = use(s)) {
                        while (1) {
                                MYSQL_ROW d = result.fetch_raw_row();
                                if (!d) break;
                                Row row(d, &result, result.fetch_lengths(),
                                                throw_exceptions());
                                if (!row) break;
                                con.push_back(typename Sequence::value_type(row));
                        }
                }
                else if (!result_empty()) {
                        // Underlying MySQL C API returned an empty result for this
                        // query, but it also says it should have returned
                        // something.  Reasons it can do that are given here:
                        // http://dev.mysql.com/doc/refman/5.5/en/null-mysql-store-result.html
                        // Regardless, it means the C library barfed, so we can't
                        // just return an empty result set.
                        copacetic_ = false;
                        if (throw_exceptions()) {
                                throw UseQueryError("Bogus empty result");
                        }
                }
                // else, it was *supposed* to return nothing, because query was
                // an INSERT, CREATE, etc. sort.  So, leave con untouched.
        }

        template <class Seq>
        void storein_sequence(Seq& con, SQLQueryParms& p)
        {
                storein_sequence(con, str(p));
        }

        template <class Set>
        void storein_set(Set& con)
        {
                storein_set(con, str(template_defaults));
        }

        template <class Set>
        void storein_set(Set& con, const SQLTypeAdapter& s)
        {
                if (UseQueryResult result = use(s)) {
                        while (1) {
                                MYSQL_ROW d = result.fetch_raw_row();
                                if (!d) break;
                                Row row(d, &result, result.fetch_lengths(),
                                                throw_exceptions());
                                if (!row) break;
                                con.insert(typename Set::value_type(row));
                        }
                }
                else if (!result_empty()) {
                        // Underlying MySQL C API returned an empty result for this
                        // query, but it also says it should have returned
                        // something.  Reasons it can do that are given here:
                        // http://dev.mysql.com/doc/refman/5.5/en/null-mysql-store-result.html
                        // Regardless, it means the C library barfed, so we can't
                        // just return an empty result set.
                        copacetic_ = false;
                        if (throw_exceptions()) {
                                throw UseQueryError("Bogus empty result");
                        }
                }
                // else, it was *supposed* to return nothing, because query was
                // an INSERT, CREATE, etc. sort.  So, leave con untouched.
        }

        template <class Set>
        void storein_set(Set& con, SQLQueryParms& p)
        {
                storein_set(con, str(p));
        }

        template <class Container>
        void storein(Container& con)
        {
                storein(con, str(template_defaults));
        }

        template <class T>
        void storein(T& con, SQLQueryParms& p)
        {
                storein(con, str(p));
        }

        template <class T>
        void storein(std::vector<T>& con, const SQLTypeAdapter& s)
        {
                storein_sequence(con, s);
        }

        template <class T>
        void storein(std::deque<T>& con, const SQLTypeAdapter& s)
        {
                storein_sequence(con, s);
        }

        template <class T>
        void storein(std::list<T>& con, const SQLTypeAdapter& s)
        {
                storein_sequence(con, s);
        }

#if defined(HAVE_EXT_SLIST)
        template <class T>
        void storein(__gnu_cxx::slist<T>& con, const SQLTypeAdapter& s)
        {
                storein_sequence(con, s);
        }
#elif defined(HAVE_GLOBAL_SLIST)
        template <class T>
        void storein(slist<T>& con, const SQLTypeAdapter& s)
        {
                storein_sequence(con, s);
        }
#elif defined(HAVE_STD_SLIST)
        template <class T>
        void storein(std::slist<T>& con, const SQLTypeAdapter& s)
        {
                storein_sequence(con, s);
        }
#endif

        template <class T>
        void storein(std::set<T>& con, const SQLTypeAdapter& s)
        {
                storein_set(con, s);
        }

        template <class T>
        void storein(std::multiset<T>& con, const SQLTypeAdapter& s)
        {
                storein_set(con, s);
        }

        template <class T>
        Query& update(const T& o, const T& n)
        {
                reset();

                // Cast required for VC++ 2003 due to error in overloaded operator
                // lookup logic.  For an explanation of the problem, see:
                // http://groups-beta.google.com/group/microsoft.public.vc.stl/browse_thread/thread/9a68d84644e64f15
                MYSQLPP_QUERY_THISPTR << std::setprecision(16) <<
                                "UPDATE `" << o.table() << "` SET " << n.equal_list() <<
                                " WHERE " << o.equal_list(" AND ", sql_use_compare);
                return *this;
        }

        template <class T>
        Query& insert(const T& v)
        {
                reset();

                MYSQLPP_QUERY_THISPTR << std::setprecision(16) <<
                                "INSERT INTO `" << v.table() << "` (" <<
                                v.field_list() << ") VALUES (" <<
                                v.value_list() << ')';
                return *this;
        }

        template <class Iter>
        Query& insert(Iter first, Iter last)
        {
                reset();

                if (first != last) {
                        // Build SQL for first item in the container.  It's special
                        // because we need the table name and field list.
                        MYSQLPP_QUERY_THISPTR << std::setprecision(16) <<
                                        "INSERT INTO `" << first->table() << "` (" <<
                                        first->field_list() << ") VALUES (" <<
                                        first->value_list() << ')';

                        // Now insert any remaining container elements.  Be careful
                        // hacking on the iterator use here: we want it to work
                        // with containers providing only a forward iterator.
                        Iter it = first;
                        while (++it != last) {
                                MYSQLPP_QUERY_THISPTR << ",(" << it->value_list() << ')';
                        }
                }

                return *this;
        }

        template <class Iter, class InsertPolicy>
        Query& insertfrom(Iter first, Iter last, InsertPolicy& policy)
        {
                bool success = true;
                bool empty = true;

                reset();

                if (first == last) {
                        return *this;   // empty set!
                }

                typename InsertPolicy::access_controller ac(*conn_);
                
                for (Iter it = first; it != last; ++it) {
                        if (policy.can_add(int(tellp()), *it)) {
                                if (empty) {
                                        MYSQLPP_QUERY_THISPTR << std::setprecision(16) <<
                                                "INSERT INTO `" << it->table() << "` (" <<
                                                it->field_list() << ") VALUES (";
                                } 
                                else {
                                        MYSQLPP_QUERY_THISPTR << ",(";
                                }

                                MYSQLPP_QUERY_THISPTR << it->value_list() << ')';

                                empty = false;
                        } 
                        else {
                                // Execute what we've built up already, if there is anything
                                if (!empty) {
                                        if (!exec()) {
                                                success = false;
                                                break;
                                        }

                                        empty = true;
                                }

                                // If we _still_ can't add, the policy is too strict
                                if (policy.can_add(int(tellp()), *it)) {
                                        MYSQLPP_QUERY_THISPTR << std::setprecision(16) <<
                                                "INSERT INTO `" << it->table() << "` (" <<
                                                it->field_list() << ") VALUES (" <<
                                                it->value_list() << ')';

                                        empty = false;
                                } 
                                else {
                                        // At this point all we can do is give up
                                        if (throw_exceptions()) {
                                                throw BadInsertPolicy("Insert policy is too strict");
                                        }

                                        success = false;
                                        break;
                                }
                        }
                }

                // We might need to execute the last query here.
                if (success && !empty && !exec()) {
                        success = false;
                }

                if (success) {
                        ac.commit();
                } 
                else {
                        ac.rollback();
                }

                return *this;
        }

        template <class Iter, class InsertPolicy>
        Query& replacefrom(Iter first, Iter last, InsertPolicy& policy)
        {
                bool success = true;
                bool empty = true;

                reset();

                if (first == last) {
                        return *this;   // empty set!
                }

                typename InsertPolicy::access_controller ac(*conn_);

                for (Iter it = first; it != last; ++it) {
                        if (policy.can_add(int(tellp()), *it)) {
                                if (empty) {
                                        MYSQLPP_QUERY_THISPTR << std::setprecision(16) <<
                                                "REPLACE INTO `" << it->table() << "` (" <<
                                                it->field_list() << ") VALUES (";
                                }
                                else {
                                        MYSQLPP_QUERY_THISPTR << ",(";
                                }

                                MYSQLPP_QUERY_THISPTR << it->value_list() << ')';

                                empty = false;
                        }
                        else {
                                // Execute what we've built up already, if there is anything
                                if (!empty) {
                                        if (!exec()) {
                                                success = false;
                                                break;
                                        }

                                        empty = true;
                                }

                                // If we _still_ can't add, the policy is too strict
                                if (policy.can_add(int(tellp()), *it)) {
                                        MYSQLPP_QUERY_THISPTR << std::setprecision(16) <<
                                                "REPLACE INTO `" << it->table() << "` (" <<
                                                it->field_list() << ") VALUES (" <<
                                                it->value_list() << ')';

                                        empty = false;
                                }
                                else {
                                        // At this point all we can do is give up
                                        if (throw_exceptions()) {
                                                throw BadInsertPolicy("Insert policy is too strict");
                                        }

                                        success = false;
                                        break;
                                }
                        }
                }

                // We might need to execute the last query here.
                if (success && !empty && !exec()) {
                        success = false;
                }

                if (success) {
                        ac.commit();
                }
                else {
                        ac.rollback();
                }

                return *this;
        }

        template <class T>
        Query& replace(const T& v)
        {
                reset();

                MYSQLPP_QUERY_THISPTR << std::setprecision(16) <<
                                "REPLACE INTO `" << v.table() << "` (" <<
                                v.field_list() << ") VALUES (" << v.value_list() << ')';
                return *this;
        }

        template <class Iter>
        Query& replace(Iter first, Iter last)
        {
                reset();
                if (first != last) {
                        // Build SQL for first item in the container.  It's special
                        // because we need the table name and field list.
                        MYSQLPP_QUERY_THISPTR << std::setprecision(16) <<
                                        "REPLACE INTO " << first->table() << " (" <<
                                        first->field_list() << ") VALUES (" <<
                                        first->value_list() << ')';

                        // Now insert any remaining container elements.  Be careful
                        // hacking on the iterator use here: we want it to work
                        // with containers providing only a forward iterator.
                        Iter it = first;
                        while (++it != last) {
                                MYSQLPP_QUERY_THISPTR << ",(" << it->value_list() << ')';
                        }
                }

                return *this;
        }       

#if !defined(DOXYGEN_IGNORE)
        // Declare the remaining overloads.  These are hidden down here partly
        // to keep the above code clear, but also so that we may hide them
        // from Doxygen, which gets confused by macro instantiations that look
        // like method declarations.
        mysql_query_define0(std::string, str)
        mysql_query_define0(SimpleResult, execute)
        mysql_query_define0(StoreQueryResult, store)
        mysql_query_define0(UseQueryResult, use)
        mysql_query_define1(storein_sequence)
        mysql_query_define1(storein_set)
        mysql_query_define1(storein)
#endif // !defined(DOXYGEN_IGNORE)

        SQLQueryParms template_defaults;

private:
        friend class SQLQueryParms;

        Connection* conn_;

        bool copacetic_;

        std::vector<SQLParseElement> parse_elems_;

        std::vector<std::string> parsed_names_;

        std::map<std::string, short int> parsed_nums_;

        std::stringbuf sbuffer_;

        void proc(SQLQueryParms& p);

        SQLTypeAdapter* pprepare(char option, SQLTypeAdapter& S, bool replace = true);
};


inline std::ostream& operator <<(std::ostream& os, Query& q)
{
        return os << q.str();
}


} // end namespace mysqlpp

#endif // !defined(MYSQLPP_QUERY_H)

---