[tcaplusdb knowledge base] Introduction to tcaplusdb tcapulogmgr tool (II)

4. updatefields

updatefields The command is used to return files and dynamically change the table structure , The command format is ./tcapulogmgr updatefields --directory= --engine-directory= --tbusid= --conf= [--speed= --seqcontinuous], among , The meanings of the first four required parameters are ：

• --directory ulog File directory

• --engine-directory Cold standby file directory

• --tbusid Indicates that you want to perform a fileback operation and dynamically change the table structure svr_id, Used to filter the corresponding... From the directory binlog file

• --conf updatefields The configuration file for the command , It specifies DirServerAddr、PassWord、 Tables to retrieve and import data and tables to convert records so file

updatefields Command configuration file template and description

<?xml version="1.0" encoding="GBK" standalone="yes" ?>
<tcapulogmgr>
​
    <!-- Dynamically change the configuration of the table structure -->
    <UpdateFieldsCfg UpdateFieldsCfgNum="1">
        <!--SourceAppID、SourceZoneID、SourceTableName Used to specify the business of the data table to be archived ID、 District Service ID And table name -->
        <!--DestAppID、DestZoneID、DestTableName Used to specify the business to save the converted records ID、 District Service ID And table name -->
        <!--LibFile Used to specify user generated to convert the record structure so file -->
        <UpdateFieldsCfgItem  SourceAppID="2" SourceZoneID="3" SourceTableName="TestData" DestAppID="2" DestZoneID="3" DestTableName="TestData_new" LibFile="do_nothing.so"/>
        <!--PassWord Is used to specify the DestTableName Password of the business -->
        <ServiceApiCfg PassWord="**********" ConnectTimeOut="10000" RegistTableTimeOut="10000" DirServerNum="1" >
            <!--DirServerAddr Is used to specify the DestTableName Directory server address of the business -->
            <DirServerAddr>tcp://*.*.*.*:9999</DirServerAddr>
        </ServiceApiCfg>
    </UpdateFieldsCfg>
​
</tcapulogmgr>

The parameters in square brackets are optional ：

• --speed Speed control parameters

• --seqcontinuous Express binlog The serial number of must be continuous , If it is not continuous, an error will be reported

Suppose the code file used to convert the record structure is do_nothing.cpp, have access to g++ -shared -fPIC -o do_nothing.so do_nothing.cpp Generate the corresponding dynamic link library file . stay do_nothing.cpp In file , It needs to be realized according to specific requirements TransferRecord function .

TransferRecord Example of function

#include <stdio.h>
#include <stdlib.h>
#include <string>
#include <string.h>
#include <assert.h>
#include <sstream>
#include <iostream>
#include <string>
#include <vector>
#include <map>
#include <tr1/functional>
​
#define TCAPLUS_MAX_TABLE_NAME_LEN_FOR_PLUGIN 128
​
enum EnumTransRecordStatus {
    ENUM_TRANS_RECORD_SUC = 0,
    ENUM_TRANS_RECORD_NOT_EXIST = 1,
    ENUM_TRANS_RECORD_FAIL= -1,
};
​
typedef int int32_t;
​
typedef struct {
    int32_t iAppID;
    int32_t iZoneID;
    char szTableName[TCAPLUS_MAX_TABLE_NAME_LEN_FOR_PLUGIN];
    std::tr1::function<int(const char*)> pFuncForBillLog;
} TcapsvrImportCallBackPara;
​
typedef std::map<std::string, std::string> TcapFieldNameValueMap;
typedef std::vector<TcapFieldNameValueMap> VALUELIST;
typedef std::vector<EnumTransRecordStatus> STATUSLIST;
​
using namespace std;
​
extern "C" int TransferRecord(const VALUELIST& old_list,
        VALUELIST& new_list, STATUSLIST& status_list,
        TcapsvrImportCallBackPara* pCallBackPara)
{
        if (NULL == pCallBackPara)
        {
                return -1;
        }
​
        VALUELIST::const_iterator it_list;
        new_list.clear();
​
        for (it_list = old_list.begin(); it_list != old_list.end(); ++it_list)
        {
                int ret = ENUM_TRANS_RECORD_SUC;
                TcapFieldNameValueMap new_map;
                const TcapFieldNameValueMap& old_map = *it_list;
​
                TcapFieldNameValueMap::const_iterator it;
                for (it = old_map.begin(); it != old_map.end(); ++it)
                {
                        std::pair<TcapFieldNameValueMap::iterator, bool> result;
                        result = new_map.insert(std::make_pair(it->first, it->second));
                        if(!result.second)
                        {
                        status_list.push_back(ENUM_TRANS_RECORD_FAIL);
                        return -1;
                        }
                }
​
                // add new filed: platformid, use default value 0
                // int32_t platformid = 0;
                // std::string new_value((char*)&platformid, sizeof(platformid));
                // std::string new_key = "platformid";
​
                // std::pair<TcapFieldNameValueMap::iterator, bool> result = new_map.insert(std::make_pair(new_key, new_value));
                // if(!result.second)
                // {
                //         status_list.push_back(ENUM_TRANS_RECORD_FAIL);
                //         return -1;
                // }
​
                new_list.push_back(new_map);
                status_list.push_back((EnumTransRecordStatus)ret);
        }
​
        return 0;
}

Generate... According to the above function example so file , And in tcapulogmgr_cfg.xml After configuring relevant parameters in , perform ./tcapulogmgr updatefields --directory=/txh/ulog/1.2.2.1 --engine-directory=/txh --tbusid=1.2.2.1 --conf=tcapulogmgr_cfg.xml --seqcontinuous. hypothesis /txh In the configuration file SourceTableName Field of the engine file of the data table specified checkpoint by 50,/txh/ulog/1.2.2.1 The largest in the directory sequence by 60, Then the command will redo sequence stay 51 To 60 Between binlog, Yes SourceTableName Field to perform a file retrieval operation on the data table specified by the ; meanwhile , Will use so File right here 10 strip binlog Transform the corresponding record structure , Put it redo To DestTableName In the data table specified by the field .

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