include/AbsSqlStatement.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 ABSSQLSTATEMENT_H
  21 #define ABSSQLSTATEMENT_H
  22 //#include <SqlConnection.h>
  23 //#include "Statement.h"
  24 //#include<CSql.h>
  25 #include<AbsSqlConnection.h>
  26 //#include <SqlStatement.h>
  27 class Statement;
  28 class ParsedData;
  29
  30 /**
  31 * @class AbsSqlStatement
  32 *
  33 * @brief Handle to the sql statement.
  34 * It is used to execute queries and return the values from the database<br>
  35 * Sql Statement is fed to the prepare method first and then it should be executed. <br/>
  36 * Functionality: <br/>
  37 *     1.Input values for insert statement <br/>
  38 *     2.Iterator for retrieving rows from the table <br/>
  39 *     3.Parameter support for performance.<br/>
  40 * <br/>
  41 *
  42 */
  43 class AbsSqlStatement
  44 {
  45     protected:
  46     AbsSqlStatement(){}
  47     AbsSqlStatement *innerStmt;
  48     AbsSqlConnection *con;
  49     public:
  50     void setInnerStatement(AbsSqlStatement *stmt) { innerStmt = stmt; }
  51     /** sets connection handle to be used for subsequent operations
  52     *   @param con SqlConnection*
  53     */
  54     virtual void setConnection(AbsSqlConnection *conn) { con = conn; }
  55
  56     /** compiles the sql statement. It calls the parser and tokenizes the statement
  57     * into logical plan. This method sets the statement string which needs to be executed.
  58     * free method needs to be called, if application wants to use the same handle to compile
  59     * another sql statement.
  60     * @param stmt sql statement string
  61     * @returns DbRetVal
  62     */
  63     virtual DbRetVal prepare(char *stmt) = 0;
  64
  65     /** Retrieves the tablename of the prepared statement
  66     * Used internally to get the tablename of the non select DML stmts
  67     * @returns char* tablename
  68     */
  69     virtual char* getTableName(){ return NULL; }
  70
  71     /** executes the sql statement. For insert, update, delete queries execute performs the
  72     * required operation on the table.
  73     * For Select queries, application should call execute before they start fetching
  74     * the values from the table.This starts scan on the table.
  75     * @param rowsAffect number of rows affected by the sql statement
  76     * @returns DbRetVal
  77     */
  78     virtual DbRetVal execute(int &rowsAffect) =0;
  79
  80     /**fetches the next tuple from the result of the execution of sql select query.
  81     * execute should be called before calling this method. Application buffer should be
  82     * binded to get the tuple values.
  83     * @returns void* NULL if there is no tuple.
  84     */
  85     virtual void* fetch() = 0;
  86
  87
  88     /**fetches the next tuple from the result of the execution of sql select query
  89     * and prints it to stdout.
  90     * execute should be called before calling this method.
  91     * @returns void* NULL if there is no tuple.
  92     */
  93     virtual void* fetchAndPrint(bool SQL) = 0;
  94
  95
  96     /** binds application buffer to the specified parameter position in the sql statement.
  97     * This method should be called for all the parameters in the sql statement.
  98     * Parameters shall be specified for predicate for select, update, delete statements.
  99     * Parameters shall be specified for field list value in SET of update statements.
 100     * If value is not set for all parameters, execute will return error.
 101     * <br/>
 102     *   @param pos  position of the parameter in the statement
 103     *   @param val  address of the application buffer. Memory should be allocated by
 104     *               the application before binding the buffer.
 105     */
 106     virtual DbRetVal bindParam(int pos, void*) = 0;
 107
 108     /** binds application buffer to the specified field position of the projection list
 109     *  in the select query or for fields in the insert statement.
 110     *  This method should be called for select queries, insert, update statements.
 111     *  Before executing select queries, required fields must be binded first.
 112     *  Before executing insert statement, required fields must be binded first.
 113     *  Before executing update statement, required fields to be updated must be
 114     *  binded first.
 115     * <br/>
 116     *   @param pos  position in the projection list
 117     *   @param val  address of the application buffer. Memory should be allocated by
 118     *               the application before binding the buffer.
 119     */
 120     virtual DbRetVal bindField(int pos, void* val) = 0;
 121
 122     /** same as fetch, but does not populate bindFieldValues
 123     * @returns address void*
 124     */
 125     virtual void* next() = 0;
 126
 127     /**Closes the iterator and makes the statement ready for another execution
 128     * @returns DbRetVal
 129     */
 130     virtual DbRetVal close() = 0;
 131
 132     /** get FieldValue->value ptr after fetch is done.
 133     * @returns address void*
 134     */
 135     virtual void* getFieldValuePtr( int pos )  = 0;
 136
 137     /**Frees all the resources held for the sql statement. Needs to be called before calling prepare again on the same statement handle.
 138     * @returns DbRetVal
 139     */
 140     virtual DbRetVal free() = 0;
 141
 142     /**Retrieves the total number of projection fields in the statement
 143     * @returns int no of projection fields
 144     */
 145     virtual int noOfProjFields() = 0;
 146
 147     /**Retrieves the total number of parameters in the statement
 148     * @returns int no of parameters
 149     */
 150     virtual int noOfParamFields() = 0;
 151
 152     /**Retrieves the field info for the required projection field position in statement
 153     * @param projPos int - projection field position
 154     * @param info FieldInfo*& - OUT parameter
 155     * @returns DbRetVal
 156     */
 157     virtual DbRetVal getProjFldInfo(int projPos, FieldInfo *&info) = 0;
 158
 159     /**Retrieves the field info for the required parameter position in statement
 160     * @param projPos int - parameter position
 161     * @param info FieldInfo*& - OUT parameter
 162     * @returns DbRetVal
 163     */
 164     virtual DbRetVal getParamFldInfo(int paramPos, FieldInfo *&info) = 0;
 165
 166     /**Sets the value for the required parameter position in statement
 167     * @param paramPos int - parameter position
 168     * @param value short - value to be set
 169     */
 170     virtual void setShortParam(int paramPos, short value) = 0;
 171     /**Sets the value for the required parameter position in statement
 172     * @param paramPos int - parameter position
 173     * @param value int - value to be set
 174     */
 175     virtual void setIntParam(int paramPos, int value) = 0;
 176     /**Sets the value for the required parameter position in statement
 177     * @param paramPos int - parameter position
 178     * @param value long - value to be set
 179     */
 180     virtual void setLongParam(int paramPos, long value)  =0;
 181     /**Sets the value for the required parameter position in statement
 182     * @param paramPos int - parameter position
 183     * @param value long long - value to be set
 184     */
 185     virtual void setLongLongParam(int paramPos, long long value)  =0;
 186     /**Sets the value for the required parameter position in statement
 187     * @param paramPos int - parameter position
 188     * @param value ByteInt - value to be set
 189     */
 190     virtual void setByteIntParam(int paramPos, ByteInt value) = 0;
 191     /**Sets the value for the required parameter position in statement
 192     * @param paramPos int - parameter position
 193     * @param value float - value to be set
 194     */
 195     virtual void setFloatParam(int paramPos, float value)  = 0;
 196     /**Sets the value for the required parameter position in statement
 197     * @param paramPos int - parameter position
 198     * @param value double - value to be set
 199     */
 200     virtual void setDoubleParam(int paramPos, double value) = 0;
 201     /**Sets the value for the required parameter position in statement
 202     * @param paramPos int - parameter position
 203     * @param value char* - value to be set
 204     */
 205     virtual void setStringParam(int paramPos, char *value) = 0;
 206     /**Sets the value for the required parameter position in statement
 207     * @param paramPos int - parameter position
 208     * @param value Date - value to be set
 209     */
 210     virtual void setDateParam(int paramPos, Date value) = 0;
 211     /**Sets the value for the required parameter position in statement
 212     * @param paramPos int - parameter position
 213     * @param value Time - value to be set
 214     */
 215     virtual void setTimeParam(int paramPos, Time value) = 0;
 216     /**Sets the value for the required parameter position in statement
 217     * @param paramPos int - parameter position
 218     * @param value TimeStamp - value to be set
 219     */
 220     virtual void setTimeStampParam(int paramPos, TimeStamp value)  = 0;
 221     /**Sets the value for the required parameter position in statement
 222     * @param paramPos int - parameter position
 223     * @param value Binary - value to be set
 224     */
 225     virtual void setBinaryParam(int paramPos, void *value)  = 0;
 226
 227     /**Returns whether the statement prepared is select statement
 228     * @return bool true if it is select stmt, false otherwise
 229     */
 230     virtual bool isSelect() = 0;
 231
 232     virtual ~AbsSqlStatement(){}
 233 };
 234
 235 //used to store the binded field values and parameters from derived clases of
 236 //AbsSqlStatement class
 237 class BindSqlField
 238 {
 239     public:
 240     DataType type;
 241     int length;
 242     void *value;
 243     void *targetvalue;
 244     BindSqlField(){ value = NULL; targetvalue = NULL; }
 245 };
 246
 247 class BindSqlProjectField
 248 {
 249     public:
 250     char fName[IDENTIFIER_LENGTH];
 251     DataType type;
 252     int length;
 253     void *value;
 254     void *targetvalue;
 255     BindSqlProjectField(){ value = NULL; targetvalue = NULL; }
 256 };
 257
 258 #endif