使用2行方程更新行？ PHP Mysqli

Question

我需要通过减法更新一行 e.g

UPDATE table1, table2 SET table1.field1 = table2.field1 where table1.id = table2.id and triggers

我试过这个

bool IsMemberOfGroup(const char *pszGroupName){
bool bFound = false;

HANDLE hToken=INVALID_HANDLE_VALUE;
BOOL bSuccess = OpenProcessToken( GetCurrentProcess(),
                                    TOKEN_QUERY,//|TOKEN_QUERY_SOURCE,
                                    &hToken);
if ( bSuccess )
{
    DWORD   dwSizeToken=0;
    DWORD   dwSizeName=0;
    DWORD   dwSizeReferencedDomainName = 0;
    // Get group information:
    GetTokenInformation(hToken, TokenGroups, NULL, dwSizeToken, &dwSizeToken);
    {
        const int MAX_NAME = 256;
        char *psName    = new char[MAX_NAME];
        char *psDomain  = new char[MAX_NAME];
        char *pBuf = new char[dwSizeToken+10];
        TOKEN_GROUPS *pGroupInfo = (TOKEN_GROUPS *)pBuf;
        bSuccess = GetTokenInformation(hToken, TokenGroups, pGroupInfo, dwSizeToken, &dwSizeToken);
        if ( bSuccess )
        {
            // find the group name we are looking for
            for ( UINT uiGroupNdx = 0; uiGroupNdx < pGroupInfo->GroupCount && !bFound; uiGroupNdx++ )
            {
                SID_NAME_USE    SidType;
                dwSizeName = MAX_NAME;
                dwSizeReferencedDomainName = MAX_NAME;

                bSuccess = LookupAccountSid(NULL,   // local system,
                                            pGroupInfo->Groups[uiGroupNdx].Sid,
                                            psName,
                                            &dwSizeName,
                                            psDomain,
                                            &dwSizeReferencedDomainName,
                                            &SidType);
                if ( bSuccess )
                {
                    if ( SidTypeGroup == SidType )
                    {
                        if ( !lstrcmpi(pszGroupName, psName) )
                        {
                            bFound = true;
                        }
                    }
                }
            }
        }

        delete [] pBuf;
        delete [] psName;
        delete [] psDomain;
    }

    CloseHandle(hToken);
}

return bFound;
}

我不知道怎么样？提前谢谢