我正在尝试获取存储在修改日期最早的表中的唯一文件名。
.bash_profilePro * C代码：
EXEC SQL AT DECLARE CtrlIndexTLOGNames_cursor CURSOR FOR
SELECT cDataSrcFileName
FROM SC_CTRL_XMLBUFFER
GROUP BY cDataSrcFileName
ORDER BY MAX(modifieddatetime) asc;
EXEC SQL FETCH CtrlIndexTLOGNames_cursor INTO :s_cDataSrcFileName;
运行此查询时，我得到多行具有唯一文件名的信息。但是，当我使用while循环在C代码中使用该函数时，它总是返回第一行，而不返回其他文件名。
您能告诉我这是怎么回事吗？
在C模块中，我称为Pro * C函数
BOOLEAN CXYZ::GetSCCtrlTLOGFileName()
{
EXEC SQL BEGIN DECLARE SECTION;
char cDataSrcFileName[SZ_FILENAME+30];
char cSetSortorder[5];
char s_cAtTable[80];
EXEC SQL END DECLARE SECTION;
BOOLEAN bOpenFail=false;
BOOLEAN bRet=false;
//char s_append[500];
sqlca.sqlcode = null;
// Always start with a clean error structure
ClearLastError();
// Make sure that we close the cursor if it is opened
CloseCursor();
ClearLastError();
// Make sure it is OK to proceed
if (m_bDBConn)
{
// Next check to see that DB is available
memset(s_cAtTable, 0, sizeof(s_cAtTable));
if (m_pSup->DBActive(m_lDBType))
m_pSup->DBAtString(m_lDBType, s_cAtTable, sizeof(s_cAtTable));
else
m_lDBType=DAI_PRIMARY;
// Here we access the appropriate table
if (m_lDBType == DAI_PRIMARY)
{
// Get the row count from the table
EXEC SQL DECLARE CtrlIndexTLOGNames_cursor CURSOR FOR
SELECT cDataSrcFileName
FROM SC_CTRL_XMLBUFFER
GROUP BY cDataSrcFileName
ORDER BY MAX(modifieddatetime) asc;
// Check to see if the cursor declare succeeded
if (sqlca.sqlcode == 0)
{
EXEC SQL OPEN CtrlIndexTLOGNames_cursor;
m_lCursorCode=SCCURCTRLXMLBUFFER;
m_bCursorOpen=true;
bRet = true;
}
else
bOpenFail=true;
}
else
{
EXEC SQL AT :s_cAtTable DECLARE CtrlIndexTLOGNames_cursor_B CURSOR FOR
SELECT cDataSrcFileName
FROM SC_CTRL_XMLBUFFER
GROUP BY cDataSrcFileName
ORDER BY MAX(modifieddatetime) asc;
// Check to see if the cursor declare succeeded
if (sqlca.sqlcode == 0)
{
EXEC SQL OPEN CtrlIndexTLOGNames_cursor_B;
m_lCursorCode=SCCURCTRLXMLBUFFER_B;
m_bCursorOpen=true;
bRet = true;
}
else
bOpenFail=true;
}
// Check to make sure the open succeeded
if(!bOpenFail)
{
if (sqlca.sqlcode == 0)
bRet=true;
else
{
// Report the failure information
sprintf(m_cLastError, (char *)"RTPSC CtrlIndexTLOGNames CURSOR open failed[%d]:", sqlca.sqlcode);
// Here we append the RDBMS string
strncat(m_cLastError, sqlca.sqlerrm.sqlerrmc, sizeof(m_cLastError)-(strlen(m_cLastError)+2));
// Here we set the appropriate control information
m_lLastError = sqlca.sqlcode;
m_bDBConn=false;
m_pSup->Show(VBL_MINIMAL,m_cLastError);
}
}
else
{
// Report the failure information
sprintf(m_cLastError, (char *)"RTP5003E:CtrlIndexTLOGNames CURSOR declaration failed[%d]:", sqlca.sqlcode);
// Here we append the RDBMS string
strncat(m_cLastError, sqlca.sqlerrm.sqlerrmc, sizeof(m_cLastError)-(strlen(m_cLastError)+2));
// Here we set the appropriate control information
m_lLastError = sqlca.sqlcode;
m_bDBConn=false;
m_pSup->Show(VBL_MINIMAL,m_cLastError);
}
}
else
{
strcpy(m_cLastError, (char *)"RTP9101E:Transaction class was not properly initialized.");
m_lLastError=EFAULT;
}
// Close out an ERROR'd cursor
if (!bRet) CloseCursor();
// Return the results of this action
return(bRet);
}
BOOLEAN CZYZ::GetSCCtrlNextTLOGFileName( char *&pFileName)
{
EXEC SQL BEGIN DECLARE SECTION;
char s_cDataSrcFileName[SZ_FILENAME+35];
char s_cAtTable[80];
EXEC SQL END DECLARE SECTION;
BOOLEAN bRet=false;
long lDataSize;
// Clear out the last error before diving in to the process
ClearLastError();
// Make sure that the caller's storage starts out clean
pFileName=(char *)null;
// Next make sure we have access to the database
if (m_bDBConn && (m_lCursorCode == SCCURCTRLXMLBUFFER || m_lCursorCode == SCCURCTRLXMLBUFFER_B))
{
// Next check to see that DB is available
memset(s_cAtTable, 0, sizeof(s_cAtTable));
if (m_pSup->DBActive(m_lDBType))
m_pSup->DBAtString(m_lDBType, s_cAtTable, sizeof(s_cAtTable));
else
m_lDBType=DAI_PRIMARY;
if (m_lCursorCode == SCCURCTRLXMLBUFFER)
{
//printf("Inside m_lCursorCode == SCCURCTRLXMLBUFFER condition\n");
// Pull the information back from the database
EXEC SQL FETCH CtrlIndexTLOGNames_cursor INTO :s_cDataSrcFileName;
}
else
{
//printf("Inside m_lCursorCode == SCCURCTRLXMLBUFFER_B condition\n");
// Pull the information back from the database
EXEC SQL FETCH CtrlIndexTLOGNames_cursor_B INTO :s_cDataSrcFileName;
}
// Check to see if the cursor declare succeeded
if (sqlca.sqlcode == 0)
{
lDataSize=strlen((char *)s_cDataSrcFileName)+2L;
// Here we allocate the storage as needed
if ((pFileName=new char[lDataSize]) != (char *)null)
{
// Here we move the data into this storage
memset(pFileName, 0, lDataSize);
strncpy(pFileName, s_cDataSrcFileName, lDataSize-1L);
bRet=true;
CleanWhiteSpace(pFileName);
}
else
{
// Here we mark this failure for the caller
sprintf(m_cLastError, (char *)"RTP1000E:Memory Allocation Failed requesting %lu bytes (rc=%ld).", lDataSize, errno);
m_lLastError=ENOMEM;
bRet=false;
}
}
else if (sqlca.sqlcode != DBERR_NOTFOUND && sqlca.sqlcode != DBERR_NODATAFOUND)
{
// Report the failure information
sprintf(m_cLastError, (char *)"RTP8323E:GLOAD CtrlIndexTLOGNames CURSOR fetch failed[%d]:", sqlca.sqlcode);
// Here we append the RDBMS string
strncat(m_cLastError, sqlca.sqlerrm.sqlerrmc, sizeof(m_cLastError)-(strlen(m_cLastError)+2));
// Here we set the appropriate control information
m_lLastError = sqlca.sqlcode;
m_bDBConn=false;
m_pSup->Show(VBL_MINIMAL,m_cLastError);
bRet=false;
}
if (!bRet)
{
// Here is the cursor close
CloseCursor();
}
}
else
{
strcpy(m_cLastError, (char *)"RTP9101E:RTPSC class was not properly initialized.");
m_lLastError=EFAULT;
}
// Here we return the results of this action
return(bRet);
}
还
打开的游标数量是否有限制？
在我的环境中：
// Get list of file names
if(!CXYZ.GetSCCtrlTLOGFileName())
{
printf("\n\nERROR creating cursor in SC_CTRL_XMLBUFFER Database Class:
\n%s\n\n", cErrorMsg);
return iRet=EIO;
}
while (CXYZ.GetSCCtrlNextTLOGFileName(pFile))
{
printf("UpdateWorkFlowListFromDB pFile - %s\n",pFile);
.
.
.
}
这可能是问题的原因吗？