分类: C/C++
2008-08-04 09:33:40
还有其他优势,不再一一列举。
三、实现
废话少说,下面转入正题:
针对Sybase的几个主要函数,下面概述处理办法,具体的实现参照源代码:
还有其他很多函数,但是因为我没有使用到,嘿嘿,就不作实现了。
四.移植
移植的方法很简单,将原来c/c 文件中#include "Sybfront.h" #include "sybdb.h"等引用Sybase头文件的地方去掉,更换为附件中的#include
"database_op.h",同时将附件中database_op.cxx加入到工程中,加上适当的编译语句(PROC),然后去除原来连接sybase的lib,加入oracle的lib:orasql9.lib。就可以在基本不修改源程序的情况下完成程序的移植!当然,如果你的sybase程序采用了非NTBSTRINGBIND类型的话,自己在cxx文件中加入相关的处理方式吧!祝好运!欢迎探讨。
五、技巧
下面我总结一些开发过程中使用到的一些小的技巧,各位见笑。如何充分利用 Visual C 的开发环境进行 Pro*C 程序开发:
相信各位对 Visual C 的集成开发环境使用比较熟吧,别告诉我你开发 Unix 下的 C/C 程序还在使用
vi、UltraEdit、EditPlus 吧!当然了,如果你坚持我也不反对,不过您老此时就不用浪费时间向下翻页了。
oracle 的 Pro*C 程序一般以 PC 结尾。而以 PC 结尾的程序,没法按照 C/C 的语法在 Visual C
的集成开发环境下显示!只是白纸黑字一片。不像 UltraEdit,可以定制使得 PC 文件按照 C/C 的语法显示(在 UltraEdit
安装目录下的 WORDFILE.TXT 文件中包含 "C CPP CC CXX H HPP AWK" 内容的后面加上 "PC"
就可以了)(也许VC有这个功能,不过我没找到)。怎么办呢?简单,修改PC文件后缀为CXX,此时,文件就按照C/C 语法进行显示了!此时,设置该文件属性页(在VC开发环境的WORKSPACE中选中该文件,按
ALT F7 )中 General 下的 Always use custom build step 为选中状态,Curstom Build 页下的
Commands/Outputs 下参考 oracle 的 example 输入相应的编译选项。记得将对应的PC后缀修改为 cxx 后缀。
database_op.cxx /* database_op.cxx 负责兼容 sybase 和 oracle对数据库的操作 */ #include "stdio.h" #include "stdlib.h" #include "string.h" #include "database_op.h" #ifdef SYBASE_PLATFORM /* * 不需要任何动作 */ #endif #ifdef MSSQL_PLATFORM #endif #ifdef ORACLE_PLATFORM EXEC SQL INCLUDE sqlca; EXEC SQL INCLUDE sqlda; EXEC SQL WHENEVER NOT FOUND CONTINUE ; EXEC SQL WHENEVER SQLWARNING CONTINUE ; EXEC SQL WHENEVER SQLERROR CONTINUE ; char dyn_statement[1024]; SQLDA *select_dp = NULL; #define MAXCOLNUM 126 #define MAXCOLVALUE 1024 char chValueBuff[MAXCOLNUM][MAXCOLVALUE]={0}; /* Maximum lengths of the _names_ of the select-list items or indicator variables. */ #define MAX_VNAME_LEN 80 #define MAX_INAME_LEN 80 typedef struct Securepair { struct Securepair *next; char *labelname; char *labelvalue; } SECLABELS; typedef struct loginrec { char chLogName[256]; char chLogPass[256]; } LOGINREC_STR; enum SQLTYPE_ENUM{SQL_NULL=0,SQL_SELECT,SQL_INSERT,SQL_UPDATE,SQL_DELETE}; struct dbprocess { sql_context ctx; char connName[20]; /*当前sql语句类型,包括查询select insert update delete,*/ /*通过在sqldata中查找上述字符串获得*/ enum SQLTYPE_ENUM sqltype ; long rowindex ; /*执行本次sql后,被取出的行的数目/下次需要取出的索引*/ long rownum ; /*本次sql得到的行数目*/ long colnum ; /*当前列数目*/ long sqlerror ;/*SQL语句错误号*/ void * ppbuff[MAXPOINTNUM] ; /*当前绑定了字段的内存地址*/ long pbufftype[MAXPOINTNUM] ; /*当前sql语句值,在执行后更改上面的rowindex,rownum,colnum*/ char sqldata[SQLDATALEN] ; }; typedef struct dbprocess DBPROC_STR; DBPROC_STR * AllOpenProcess[20]={0}; EHANDLEFUNC ehandfunc = 0 ; MHANDLEFUNC mhandfunc = 0 ; RETCODE dbinit (void) { int i ; if( select_dp ) return SUCCEED ; if ((select_dp =sqlald (MAXPOINTNUM, MAX_VNAME_LEN, MAX_INAME_LEN)) == (SQLDA *) 0) { fprintf(stderr,"Cannot allocate memory for select descriptor."); return FAIL; } select_dp->N = MAXPOINTNUM; /* Allocate the pointers to the indicator variables, and the actual data. */ for (i = 0; i < MAXPOINTNUM; i ) { select_dp->I[i] = (short *) malloc(sizeof(short)); select_dp->V[i] = (char *) malloc(1); } return SUCCEED; } void errhandlefunc() { if( ehandfunc ) (*ehandfunc)(0,0,0,0,"","") ; } void mhandlefunc() { if( mhandfunc ) (*mhandfunc)(0,0,0,0,"","","",0) ; } EHANDLEFUNC dberrhandle (EHANDLEFUNC handler) { ehandfunc = handler ; /* EXEC SQL WHENEVER SQLERROR DO errhandlefunc() ;*/ return 0 ; } MHANDLEFUNC dbmsghandle (MHANDLEFUNC handler) { mhandfunc = handler ; /* EXEC SQL WHENEVER SQLWARNING DO mhandlefunc() ;***/ return 0 ; } void * dblogin (void) { LOGINREC_STR * rec ; rec = (LOGINREC_STR*)malloc(sizeof(LOGINREC_STR)) ; if( NULL == rec ) return rec ; memset(rec,0,sizeof(LOGINREC_STR)); return rec; } RETCODE dbsetlname (LOGINREC_STR *lptr,char *values,int type) { if( NULL == lptr || NULL == values ) return FAIL ; if( (DBSETUSER != type) &&(DBSETPWD != type) ) return FAIL ; if( DBSETUSER == type ) { if( strlen(values) >= sizeof(lptr->chLogName) ) return FAIL ; strcpy( lptr->chLogName,values) ; } if( DBSETPWD == type ) { if( strlen(values) >= sizeof(lptr->chLogPass) ) return FAIL ; strcpy( lptr->chLogPass,values) ; } return SUCCEED ; } /* 该函数内进行数据库连接尝试 */ DBPROCESS *dbopen (LOGINREC_STR *logon_ptr,char *servername) { int iLen ,iIndex ; DBPROC_STR * dbprocess ; EXEC SQL BEGIN DECLARE SECTION; VARCHAR username[256]; VARCHAR password[256]; VARCHAR dbstring[256]; EXEC SQL END DECLARE SECTION; if( NULL == logon_ptr ) return NULL ; dbprocess = (DBPROC_STR*)malloc(sizeof(DBPROC_STR)); if( NULL == dbprocess ) return NULL ; memset(dbprocess,0,sizeof(DBPROC_STR)); iLen = sizeof(AllOpenProcess)/sizeof(DBPROC_STR * ); for ( iIndex = 0 ; iIndex < iLen ; iIndex ) { if( NULL == AllOpenProcess[iIndex] ) { AllOpenProcess[iIndex] = dbprocess ; sprintf(dbprocess->connName,"conn%d",iIndex); break ; } } if( iIndex == iLen ) { free(dbprocess) ; dbprocess = NULL ; } /* 此处进行连接尝试!!!!!!!!! */ strncpy((char *) username.arr, logon_ptr->chLogName, sizeof(username.arr)); username.len = strlen((char *) username.arr); strncpy((char *) password.arr, logon_ptr->chLogPass, sizeof(password.arr)); password.len = strlen((char *) password.arr); EXEC SQL CONTEXT ALLOCATE :dbprocess->ctx; EXEC SQL CONTEXT USE :dbprocess->ctx; if( NULL == servername ) { EXEC SQL CONNECT :username IDENTIFIED BY :password AT:dbprocess->connName ; } else { strncpy((char*)dbstring.arr,servername,sizeof(dbstring.arr) ) ; dbstring.len = strlen((char*)dbstring.arr); EXEC SQL CONNECT :username IDENTIFIED BY :password AT:dbprocess->connName USING :dbstring ; } if (sqlca.sqlcode < 0 ) { printf("\n%d %s\n",sqlca.sqlcode,sqlca.sqlerrm.sqlerrmc); printf("CONNECT ERROR!"); return FAIL ; } return (DBPROCESS*)dbprocess ; } void dbloginfree (LOGINREC_STR *loginptr) { if( NULL != loginptr ) { memset( loginptr,0,sizeof(LOGINREC_STR)); free(loginptr) ; } } /* 该函数仅仅拷贝命令,做简单的命令检查 */ RETCODE dbcmd (DBPROC_STR *dbproc,const char *cmdstring) { long l_len ; char * pSelect , *pInsert , *pUpdate,*pDelete ,*pMin; if( NULL == dbproc || NULL == cmdstring ) return FAIL ; /* 仅仅拷贝命令,做简单的命令检查!!!!!!!!!!!!!!!!!!!!! */ l_len = strlen(cmdstring) ; if( l_len >= sizeof(dbproc->sqldata) ) return FAIL ; memcpy( dbproc->sqldata, cmdstring , l_len 1) ; strupr(dbproc->sqldata); dbproc->colnum =0 ; dbproc->rowindex = 0 ; dbproc->rownum = 0 ; memset(dbproc->ppbuff,0,sizeof(dbproc->ppbuff)); memset(dbproc->pbufftype,0,sizeof(dbproc->pbufftype)); /*分析命令类型*/ pSelect = strstr(dbproc->sqldata,"SELECT"); pInsert = strstr(dbproc->sqldata,"INSERT"); pUpdate = strstr(dbproc->sqldata,"UPDATE"); pDelete = strstr(dbproc->sqldata,"DELETE"); pMin = dbproc->sqldata strlen(dbproc->sqldata) ; dbproc->sqltype = SQL_NULL ; if( (pSelect) && (pSelect < pMin) ) { pMin = pSelect ;dbproc->sqltype = SQL_SELECT ; } if( (pInsert) && (pInsert < pMin) ) { pMin = pInsert ;dbproc->sqltype = SQL_INSERT ; } if( (pUpdate) && (pUpdate < pMin) ) { pMin = pUpdate ;dbproc->sqltype = SQL_UPDATE ; } if( (pDelete) && (pDelete < pMin) ) { pMin = pDelete ;dbproc->sqltype = SQL_DELETE ; } if( SQL_NULL == dbproc->sqltype ) { dbproc->sqlerror = -1 ; return FAIL ; } return SUCCEED ; } /* 该函数 执行命令 */ RETCODE dbsqlexec (DBPROC_STR *dbproc) { int i,null_ok, precision, scale; EXEC SQL BEGIN DECLARE SECTION; VARCHAR chSqlStr[SQLDATALEN]; EXEC SQL END DECLARE SECTION; if( NULL == dbproc ) return FAIL ; if( SQL_NULL == dbproc->sqltype ) return FAIL ; dbproc->colnum = 0 ; dbproc->rowindex = 0 ; dbproc->rownum = 0 ; dbproc->sqlerror = 0 ; memset( dbproc->ppbuff,0,sizeof(dbproc->ppbuff) ); memset(dbproc->pbufftype,0,sizeof(dbproc->pbufftype)); strcpy(chSqlStr.arr,dbproc->sqldata); chSqlStr.len = strlen(chSqlStr.arr); if( SQL_INSERT == dbproc->sqltype || SQL_UPDATE == dbproc->sqltype || SQL_DELETE == dbproc->sqltype ) { EXEC SQL CONTEXT USE :dbproc->ctx; EXEC SQL AT :dbproc->connName execute immediate :chSqlStr ; dbproc->sqlerror = sqlca.sqlcode ; if( dbproc->sqlerror < 0 ) { printf("\n%s\n",sqlca.sqlerrm.sqlerrmc); EXEC SQL ROLLBACK ; return FAIL ; } dbproc->rownum = sqlca.sqlerrd[2] ; EXEC SQL CONTEXT USE :dbproc->ctx; EXEC SQL AT :dbproc->connName COMMIT ; return SUCCEED ; } /*采用CURSOR游标方式*/ /* 采用动态sql 4 方法 */ if( SQL_SELECT == dbproc->sqltype ) { sqlca.sqlcode = 0 ; if (sqlca.sqlcode != 0 ) { printf("\nDECLARE err = %d\n%s\n", sqlca.sqlcode , sqlca.sqlerrm.sqlerrmc); return FAIL ; } EXEC SQL CONTEXT USE :dbproc->ctx; EXEC SQL AT :dbproc->connName PREPARE SSS FROM :chSqlStr; if (sqlca.sqlcode != 0 ) { printf("\nPREPARE err = %d\n%s\n", sqlca.sqlcode , sqlca.sqlerrm.sqlerrmc); return FAIL ; } EXEC SQL CONTEXT USE :dbproc->ctx; EXEC SQL AT :dbproc->connName DECLARE CCC CURSOR FOR SSS; if (sqlca.sqlcode != 0 ) { printf("\nDECLARE CCC err = %d\n%s\n", sqlca.sqlcode , sqlca.sqlerrm.sqlerrmc); return FAIL ; } EXEC SQL CONTEXT USE :dbproc->ctx; EXEC SQL AT :dbproc->connName OPEN CCC ; if (sqlca.sqlcode != 0 ) { printf("\nOPEN CCC err = %d\n%s\n", sqlca.sqlcode , sqlca.sqlerrm.sqlerrmc); return FAIL ; } select_dp->N = MAXPOINTNUM; EXEC SQL CONTEXT USE :dbproc->ctx; EXEC SQL AT :dbproc->connName DESCRIBE SELECT LIST FOR SSS INTO select_dp; dbproc->sqlerror = sqlca.sqlcode ; if( dbproc->sqlerror < 0 ) { printf("\nerr = %d\n%s\n", sqlca.sqlcode , sqlca.sqlerrm.sqlerrmc); EXEC SQL CONTEXT USE :dbproc->ctx; EXEC SQL AT :dbproc->connName CLOSE CCC ; EXEC SQL CONTEXT USE :dbproc->ctx; EXEC SQL AT :dbproc->connName ROLLBACK ; return FAIL ; } if (select_dp->F < 0 ) { printf("\nerr = %d\n%s\n", sqlca.sqlcode , sqlca.sqlerrm.sqlerrmc); EXEC SQL CONTEXT USE :dbproc->ctx; EXEC SQL AT :dbproc->connName CLOSE CCC ; EXEC SQL CONTEXT USE :dbproc->ctx; EXEC SQL AT :dbproc->connName ROLLBACK ; return FAIL ; } if (select_dp->F > MAXPOINTNUM ) { printf("\nerr = %d\n%s\n", sqlca.sqlcode , sqlca.sqlerrm.sqlerrmc); EXEC SQL CONTEXT USE :dbproc->ctx; EXEC SQL AT :dbproc->connName CLOSE CCC ; EXEC SQL CONTEXT USE :dbproc->ctx; EXEC SQL AT :dbproc->connName ROLLBACK ; return FAIL ; } select_dp->N = select_dp->F; dbproc->colnum = select_dp->N ; /*不能直接取到所有行的数目,所以直接采用当前行加1的方式处理*/ dbproc->rownum = dbproc->rowindex 1 ; for (i = 0; i < select_dp->F; i ) { /*char title[MAX_VNAME_LEN]; */ /* Turn off high-order bit of datatype (in this example, it does not */ /* matter if the column is NOT NULL). */ sqlnul ((unsigned short *)&(select_dp->T[i]), (unsigned short *)&(select_dp->T[i]), &null_ok); /* VARCHAR2 1 char[n] NUMBER 2 char[n] ( n <= 22) INTEGER 3 int FLOAT 4 float STRING 5 char[n 1] VARNUM 6 char[n] (n <= 22) DECIMAL 7 float LONG 8 char[n] VARCHAR 9 char[n 2] ROWID 11 char[n] DATE 12 char[n] VARRAW 15 char[n] RAW 23 unsigned char[n] LONG RAW 24 unsigned char[n] UNSIGNED 68 unsigned int DISPLAY 91 char[n] LONG VARCHAR 94 char[n 4] LONG VARRAW 95 unsigned char[n 4] CHAR 96 char[n] CHARF 96 char[n] CHARZ 97 char[n 1] */ switch (select_dp->T[i]) { /* CHAR datatype: no change in length needed, except */ /* possibly for TO_CHAR conversions (not handled here). */ case 1 : break; /* NUMBER datatype: use sqlprc() to extract precision and scale. */ case 2 : sqlprc ((unsigned long *)&(select_dp->L[i]), &precision, &scale); /* Allow for maximum size of NUMBER. */ if (precision == 0) precision = 40; /* Also allow for decimal point and possible sign. */ /* convert NUMBER datatype to FLOAT if scale > 0,*/ /* INT otherwise. */ if (scale > 0) select_dp->L[i] = sizeof(float); else select_dp->L[i] = sizeof(int); break; case 8 : /* LONG datatype */ select_dp->L[i] = 240; break; case 11 : /* ROWID datatype */ case 104 : /* Universal ROWID datatype */ select_dp->L[i] = 18; break; case 12 : /* DATE datatype */ select_dp->L[i] = 9; break; case 23 : /* RAW datatype */ break; case 24 : /* LONG RAW datatype */ select_dp->L[i] = 240; break; } /* Allocate space for the select-list data values.sqlald() */ /* reserves a pointer location for V[i] but does not allocate */ /* the full space for the pointer. */ if (select_dp->T[i] != 2) { select_dp->V[i] = (char *) realloc(select_dp->V[i], select_dp->L[i] 1); } else select_dp->V[i] = (char *) realloc(select_dp->V[i], select_dp->L[i]); /* Print column headings, right-justifying number column headings. */ /* Copy to temporary buffer in case name is null-terminated */ /* strncpy(title, select_dp->S[i], select_dp->C[i]); if (select_dp->T[i] == 2) if (scale > 0) printf ("%.*s ", select_dp->L[i] 3, title); else printf ("%.*s ", select_dp->L[i], title); else printf("%-.*s ", select_dp->L[i], title); */ /* Coerce ALL datatypes except for LONG RAW and NUMBER to character. */ if (select_dp->T[i] != 24 && select_dp->T[i] != 2) select_dp->T[i] = 1; /* Coerce the datatypes of NUMBERs to float or int */ /* depending on the scale. */ if (select_dp->T[i] == 2) { if (scale > 0) select_dp->T[i] = 4; /* float */ else select_dp->T[i] = 3; /* int */ } } } return SUCCEED ; } /* 该函数判断数据库返回结果,操作DBPROC_STR的特定字段 SUCCEED NO_MORE_RESULTS */ RETCODE dbresults (DBPROC_STR *dbproc) { if( NULL == dbproc ) return NO_MORE_RESULTS; if( dbproc->sqlerror < 0 ) return NO_MORE_RESULTS ; if( dbproc->rowindex != dbproc->rownum ) return SUCCEED ; return NO_MORE_RESULTS ; } /* 绑定值,绑定存储值的位子 */ RETCODE dbbind (DBPROC_STR *dbproc,int colnum,int vartype,DBINT varlen,BYTE *destvar) { if( colnum <= 0 ) return FAIL ; if( colnum > dbproc->colnum ) return FAIL ; if( colnum >= MAXPOINTNUM ) return FAIL ; /* 当前仅支持此类型 */ if( NTBSTRINGBIND != vartype ) { printf("\n!!!!!!!!!!!!!UNKNOWN TYPE %d !!!!!!!!\n\n",vartype); exit(0);/*!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! */ } dbproc->ppbuff[colnum - 1 ] = destvar ; dbproc->pbufftype[colnum - 1 ] = vartype ; return FAIL ; } /* 获得本次执行返回多少列 */ int dbnumcols (DBPROC_STR *dbproc) { return dbproc->colnum ; } /* 将下一条值赋值到绑定的变量上 */ STATUS dbnextrow (DBPROC_STR *dbprocess) { int i ; if( NULL == dbprocess ) return NO_MORE_ROWS ; /* FETCH each row selected and print the column values. */ EXEC SQL CONTEXT USE :dbprocess->ctx; EXEC SQL WHENEVER NOT FOUND GOTO end_select_loop; EXEC SQL CONTEXT USE :dbprocess->ctx; EXEC SQL AT :dbprocess->connName FETCH CCC USING DESCRIPTOR select_dp; /* Since each variable returned has been coerced to a character string, */ /* int, or float very little processing is required here. This routine */ /* just prints out the values on the terminal. */ for (i = 0; i < select_dp->F; i ) { if( NULL == dbprocess->ppbuff[i] ) continue ; if (*select_dp->I[i] < 0) { switch(dbprocess->pbufftype[i]) { case NTBSTRINGBIND : /* if (select_dp->T[i] == 4) sprintf ("%-*c ",(int)select_dp->L[i] 3, '' ''); else printf ("%-*c ",(int)select_dp->L[i], '' ''); */ strcpy(dbprocess->ppbuff[i],""); break; case CHARBIND: *((char*)dbprocess->ppbuff[i]) = 0 ; break ; case INTBIND: *((int*)dbprocess->ppbuff[i]) = 0 ; break ; default: /* * ERROR ! not support type! */ dbprocess->sqlerror = -50001; return NO_MORE_ROWS ; } } else { switch(dbprocess->pbufftype[i]) { case NTBSTRINGBIND : if (select_dp->T[i] == 3) /* int datatype */ sprintf (dbprocess->ppbuff[i], "%*d", (int)select_dp->L[i], *(int *)select_dp->V[i]); else if (select_dp->T[i] == 4) /* float datatype */ sprintf (dbprocess->ppbuff[i], "%*.2f", (int)select_dp->L[i], *(float *)select_dp->V[i]); else /* character string */ sprintf (dbprocess->ppbuff[i], "%-*.*s", (int)select_dp->L[i], (int)select_dp->L[i], select_dp->V[i]); break; case CHARBIND: *((char*)dbprocess->ppbuff[i]) = *(char*) select_dp->V[i] ; break ; case INTBIND: *((int*)dbprocess->ppbuff[i]) = *(int*) select_dp->V[i] ; break ; default: /* * ERROR ! not support type! */ dbprocess->sqlerror = -50001; return NO_MORE_ROWS ; } } } return SUCCEED ; end_select_loop : dbprocess->rownum = dbprocess->rowindex ; return NO_MORE_ROWS ; } /* 判断该连接是否正常 */ DBBOOL dbdead (DBPROC_STR *a) { char chbuff[8]; chbuff[0]=''\0''; EXEC SQL WHENEVER NOT FOUND GOTO end_select_loop; EXEC SQL CONTEXT USE :a->ctx; EXEC SQL AT :a->connName SELECT ''A'' INTO :chbuff FROM DUAL ; if (''A'' != chbuff[0]) { return FAIL ; } return SUCCEED ; end_select_loop: return FAIL ; } /* 该函数释放dbopen产生的内存,同时断开数据库连接 需要进一步的考虑! */ void dbexit (void) { int i,iLen ,iIndex ; EXEC SQL WHENEVER SQLERROR CONTINUE; iLen = sizeof(AllOpenProcess)/sizeof(DBPROC_STR * ); for ( iIndex = 0 ; iIndex < iLen ; iIndex ) { if( NULL != AllOpenProcess[iIndex] ) { /* * 此处开始断开数据库连接!!!!!!!!!!!!!! */ EXEC SQL CONTEXT USE : AllOpenProcess[iIndex]->ctx; EXEC SQL WHENEVER NOT FOUND GOTO end_select_loop; /* Close the cursor. */ EXEC SQL AT :AllOpenProcess[iIndex]->connName CLOSE CCC; EXEC SQL AT :AllOpenProcess[iIndex]->connName COMMIT WORK RELEASE; free(AllOpenProcess[iIndex]); AllOpenProcess[iIndex] = NULL ; } } if( select_dp ) { for (i = 0; i < MAXPOINTNUM; i ) { if (select_dp->V[i] != (char *) 0) free(select_dp->V[i]); free(select_dp->I[i]); /* MAXPOINTNUM were allocated. */ } /* Free space used by the descriptors themselves. */ sqlclu(select_dp); select_dp = NULL ; } return; } #endif #ifdef MSSQL_PLATFORM #endif下载本文示例代码