include/SqlStatement.h

   1 /***************************************************************************
   2  *   Copyright (C) 2007 by Prabakaran Thirumalai   *
   3  *   praba_tuty@yahoo.com   *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  19  ***************************************************************************/
  20 #ifndef SQLSTATEMENT_H
  21 #define SQLSTATEMENT_H
  22 #include <SqlConnection.h>
  23 #include "Statement.h"
  24 //#include<CSql.h>
  25 //class Statement;
  26 class ParsedData;
  27
  28 /**
  29 * @class SqlStatement
  30 *
  31 * @brief Handle to the sql statement.
  32 * It is used to execute queries and return the values from the database<br>
  33 * Sql Statement is fed to the prepare method first and then it should be executed. <br/>
  34 * Functionality: <br/>
  35 *     1.Input values for insert statement <br/>
  36 *     2.Iterator for retrieving rows from the table <br/>
  37 *     3.Parameter support for performance.<br/>
  38 * <br/>
  39 * @author Prabakaran Thirumalai
  40 */
  41 class SqlStatement
  42 {
  43     public:
  44     /** Default constructor
  45     */
  46     SqlStatement();
  47     /** sets connection handle to be used for subsequent operations
  48     *   @param con SqlConnection*
  49     */
  50     void setConnection(SqlConnection *con);
  51
  52     /** compiles the sql statement. It calls the parser and tokenizes the statement
  53     * into logical plan. This method sets the statement string which needs to be executed.
  54     * free method needs to be called, if application wants to use the same handle to compile
  55     * another sql statement.
  56     * @param stmt sql statement string
  57     * @returns DbRetVal
  58     */
  59     DbRetVal prepare(char *stmt);
  60
  61     /** executes the sql statement. For insert, update, delete queries execute performs the
  62     * required operation on the table.
  63     * For Select queries, application should call execute before they start fetching
  64     * the values from the table.This starts scan on the table.
  65     * @param rowsAffect number of rows affected by the sql statement
  66     * @returns DbRetVal
  67     */
  68     DbRetVal execute(int &rowsAffect);
  69
  70     /**fetches the next tuple from the result of the execution of sql select query.
  71     * execute should be called before calling this method. Application buffer should be
  72     * binded to get the tuple values.
  73     * @returns void* NULL if there is no tuple.
  74     */
  75     void* fetch();
  76
  77
  78     /**fetches the next tuple from the result of the execution of sql select query
  79     * and prints it to stdout.
  80     * execute should be called before calling this method.
  81     * @returns void* NULL if there is no tuple.
  82     */
  83     void* fetchAndPrint();
  84
  85
  86     /** binds application buffer to the specified parameter position in the sql statement.
  87     * This method should be called for all the parameters in the sql statement.
  88     * Parameters shall be specified for predicate for select, update, delete statements.
  89     * Parameters shall be specified for field list value in SET of update statements.
  90     * If value is not set for all parameters, execute will return error.
  91     * <br/>
  92     *   @param pos  position of the parameter in the statement
  93     *   @param val  address of the application buffer. Memory should be allocated by
  94     *               the application before binding the buffer.
  95     */
  96     DbRetVal bindParam(int pos, void*);
  97
  98     /** binds application buffer to the specified field position of the projection list
  99     *  in the select query or for fields in the insert statement.
 100     *  This method should be called for select queries, insert, update statements.
 101     *  Before executing select queries, required fields must be binded first.
 102     *  Before executing insert statement, required fields must be binded first.
 103     *  Before executing update statement, required fields to be updated must be
 104     *  binded first.
 105     * <br/>
 106     *   @param pos  position in the projection list
 107     *   @param val  address of the application buffer. Memory should be allocated by
 108     *               the application before binding the buffer.
 109     */
 110     DbRetVal bindField(int pos, void* val);
 111
 112     /**Frees all the resources held for the sql statement. Needs to be called before calling prepare again on the same statement handle.
 113     * @returns DbRetVal
 114     */
 115     DbRetVal free();
 116
 117     /**Retrieves the total number of projection fields in the statement
 118     * @returns int no of projection fields
 119     */
 120     int noOfProjFields();
 121
 122     /**Retrieves the total number of parameters in the statement
 123     * @returns int no of parameters
 124     */
 125     int noOfParamFields();
 126
 127     /**Retrieves the field info for the required projection field position in statement
 128     * @param projPos int - projection field position
 129     * @param info FieldInfo*& - OUT parameter
 130     * @returns DbRetVal
 131     */
 132     DbRetVal getProjFldInfo(int projPos, FieldInfo *&info);
 133
 134     /**Retrieves the field info for the required parameter position in statement
 135     * @param projPos int - parameter position
 136     * @param info FieldInfo*& - OUT parameter
 137     * @returns DbRetVal
 138     */
 139     DbRetVal getParamFldInfo(int paramPos, FieldInfo *&info);
 140
 141     /**Sets the value for the required parameter position in statement
 142     * @param paramPos int - parameter position
 143     * @param value short - value to be set
 144     */
 145     void setShortParam(int paramPos, short value);
 146     /**Sets the value for the required parameter position in statement
 147     * @param paramPos int - parameter position
 148     * @param value int - value to be set
 149     */
 150     void setIntParam(int paramPos, int value);
 151     /**Sets the value for the required parameter position in statement
 152     * @param paramPos int - parameter position
 153     * @param value long - value to be set
 154     */
 155     void setLongParam(int paramPos, long value);
 156     /**Sets the value for the required parameter position in statement
 157     * @param paramPos int - parameter position
 158     * @param value long long - value to be set
 159     */
 160     void setLongLongParam(int paramPos, long long value);
 161     /**Sets the value for the required parameter position in statement
 162     * @param paramPos int - parameter position
 163     * @param value ByteInt - value to be set
 164     */
 165     void setByteIntParam(int paramPos, ByteInt value);
 166     /**Sets the value for the required parameter position in statement
 167     * @param paramPos int - parameter position
 168     * @param value float - value to be set
 169     */
 170     void setFloatParam(int paramPos, float value);
 171     /**Sets the value for the required parameter position in statement
 172     * @param paramPos int - parameter position
 173     * @param value double - value to be set
 174     */
 175     void setDoubleParam(int paramPos, double value);
 176     /**Sets the value for the required parameter position in statement
 177     * @param paramPos int - parameter position
 178     * @param value char* - value to be set
 179     */
 180     void setStringParam(int paramPos, char *value);
 181     /**Sets the value for the required parameter position in statement
 182     * @param paramPos int - parameter position
 183     * @param value Date - value to be set
 184     */
 185     void setDateParam(int paramPos, Date value);
 186     /**Sets the value for the required parameter position in statement
 187     * @param paramPos int - parameter position
 188     * @param value Time - value to be set
 189     */
 190     void setTimeParam(int paramPos, Time value);
 191     /**Sets the value for the required parameter position in statement
 192     * @param paramPos int - parameter position
 193     * @param value TimeStamp - value to be set
 194     */
 195     void setTimeStampParam(int paramPos, TimeStamp value);
 196
 197     /**Returns whether the statement prepared is select statement
 198     * @return bool true if it is select stmt, false otherwise
 199     */
 200     bool isSelect();
 201
 202     private:
 203     SqlConnection *con;
 204     Statement *stmt;
 205     ParsedData pData;
 206
 207 };
 208
 209 #endif