How to write ticks into the database? - MQL4 and MetaTrader 4

twiling1983 2010.01.28 14:01 #71

sergeev >>:

А что вы конкретно имеете в наработке по данному вопросу MS SQL?

приведите код и покажите где у вас не работает. будем разбираться.

//TheVilkas example

#include <ADOLib.mqh>

int createCnn=0;
int openCnn=0;
int Insert=0;

string StringConnection="DSN=dbForex;UID=sa;PWD=;";

int init()
{

CloseConnection();
DestroyConnection();

int createCnn=CreateConnection();
Sleep(10);

int openCnn=OpenConnection(StringConnection,adUseClient,0);
Sleep(10);

return(0);
}

//job example:

int start()
{
//this is just in case a connection is closed or "gone bad" - there are enough reasons
if (createCnn<=0 || IsOpenConnection()==0)
{
createCnn=0;
openCnn=0;

CloseConnection();
Sleep(10);

DestroyConnection();
Sleep(10);

createCnn=CreateConnection();
Sleep(30);
}

if (createCnn>0 &&(openCnn<=0 || IsOpenConnection()==0 || Insert==0))
{
openCnn=0;

CloseConnection();
Sleep(10);

openCnn=OpenConnection(StringConnection,adUseClient,0);
Sleep(30);
}

//and then write ticks into the database

string Company=AccountCompany();
string Symb=Symbol();

//insertion code works
/*
string CommandText="INSERT INTO Rates (TimeCurrent,AccountCompany,Symb,DateTimeRate,Ask,Bid) "+
"VALUES("+TimeCurrent()+",'"+Company+"','"+Symb+"','"+DateTimeRate+"',"+Ask+","+Bid+")";
Execute(CommandText,adAsyncFetch);
Sleep(15);
*/
//I want to receive data from the database

string CommandText="select ask from test where ask='1.4560'";
string text=Execute(CommandText,adAsyncFetch);
Comment(text);

Sleep(15);

//returns 1;
}

//+------------------------------------------------------------------+
//| expert deinitialization function |
//+------------------------------------------------------------------+
int deinit()
{
CloseConnection();
DestroyConnection();

return(0);
}

how to save data [WARNING CLOSED!] Any newbie [ARCHIVE] Any rookie question,

twiling1983 2010.01.28 14:04 #72

sergeev >>:

А что вы конкретно имеете в наработке по данному вопросу MS SQL?

приведите код и покажите где у вас не работает. будем разбираться.

//Sample Graff.

//+------------------------------------------------------------------+
//| news001.mq4 |
//| Copyright © 2009, Graff |
//| |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2009, Graff"
#property link ""

#property indicator_chart_window

#define DELIM ";"
//#include <mysql.mqh>

#import "libmysql.dll"
int mysql_init(int db);
int mysql_errno(int TMYSQL);
int mysql_real_connect( int TMYSQL,string host,string user,string password, string DB,int port,int socket,int clientflag);
int mysql_real_query(int TMSQL,string query,int length);
void mysql_close(int TMSQL);

int mysql_store_result(int TMSQL);
string mysql_fetch_row(int result);
int mysql_num_rows(int result);
void mysql_free_result(int result);

//#import

int mysql;

int mTicket, mType;
string mSymbol;
double mLots, mOpen, mClose, mStopLoss, mTakeProfit;

//+------------------------------------------------------------------+
//| Custom indicator initialization function |
//+------------------------------------------------------------------+
int init()
{
//---- indicators
string row;
connect();
string query="Select ask from calendar WHERE ask = '1.4567'";
int length=StringLen(query);
mysql_real_query(mysql,query,length);
int result = mysql_store_result(mysql);
int numOfRows = mysql_num_rows(result);
for (int i=0;i<numOfRows;i++) {
row = mysql_fetch_row(result);
Print(row);

Comment(row);

//returns a normal value but at the beginning of the load

Use libmysql.dll directly to Retrieving a single value Connecting to a MySql

Christo Tsvetanov 2010.01.28 14:43 #73

IMHO - you need to write your own dll. Too many language constructs are missing in MQL4 - MQL5 promises more.

--- 2010.01.28 14:48 #74

IMHO is not helpful here.

What about the documentation. What does Execute return?

I think it returns a boolean value. Your text says 1. It means that it was executed correctly.

You have to search through the recordings.

What RefreshRates() updates Problem with pending orders Any questions from newcomers

Christo Tsvetanov 2010.01.28 15:08 #75

Here' s a demonstration of how to work through ADO - might come in handy - quick and easy to do

Serge 2010.01.28 15:14 #76

I have an excellent connection between MT4 and MYSQL. No other libraries except libmySQL.dll are used.

Atg Vasylchenko 2010.05.20 08:44 #77

Please tell me, who knows, is it possible to integrate MetaTrader 5 with Oracle DBS?

Александр 2010.05.20 11:55 #78

Twilight >>:

А как осуществить чтение из БД?

ADOLib.mqh looks like this:

// Constants for enum CursorTypeEnum

#define adOpenUnspecified 4294967295 //$FFFFFFFFFF;
#define adOpenForwardOnly 0 //$000000000000;
#define adOpenKeyset 1 //$00000001;
#define adOpenDynamic 2 //$00000002;
#define adOpenStatic 3 //$00000003;

// Constants for enum LockTypeEnum

#define adLockUnspecified 4294967295 //$FFFFFFFFFF;
#define adLockReadOnly 1 //$00000001
#define adLockPessimistic 2 //$00000002;
#define adLockOptimistic 3 //$$00000003;
#define adLockBatchOptimistic 4 //$00000004;

// Constants for enum ExecuteOptionEnum

#define adOptionUnspecified 4294967295 //$FFFFFFFFFF;
#define adAsyncExecute 16 //$00000010;
#define adAsyncFetch 32 //$00000020;
#define adAsyncFetchNonBlocking 64 //$00000040;
#define adExecuteNoRecords 128 //$00000080;
#define adExecuteStream 296 //$00000400;
#define adExecuteRecord 2048 //$00000800;

// Constants for enum CursorLocationEnum

#define adUseNone 1 //$00000001;
#define adUseServer 2 //$00000002;
#define adUseClient 3 //$00000003;
#define adUseClientBatch 3 //$00000003;

// Constants for enum CommandTypeEnum

#define adCmdUnspecified 4294967295 //$FFFFFFFFFF;
#define adCmdUnknown 8 //$00000008;
#define adCmdText 1 //$00000001;
#define adCmdTable 2 //$00000002;
#define adCmdStoredProc 4 //$00000004;
#define adCmdFile 256 //$00000100;
#define adCmdTableDirect 512 //$00000200;

#import "ADOLib.dll".
int CreateConnection();
int DestroyConnection();
int OpenConnection(string ConnectionString,int CursorLocation,int CommandTimeout);
int CloseConnection();
int IsOpenConnection();
int Execute(string CommandText,int ExecuteOption);
int BeginTrans();
int CommitTrans();
int RollbackTrans();
int OpenTable(string Qry,int CursorLocation,int CursorType,int LockType,int Options);
int CloseTable();
int Requery();
int Update();
int UpdateBatch();
int Cancel();
int CancelBatch();
int CancelUpdate();
int Find(string Criteria,int SearchDirection,int Start);
int Filter(string Criteria);
int BOF();
int EOF();
int MoveFirst();
int MoveLast();
int MoveNext();
string TableStatus();
int FieldsCount();
string FieldName(int I);
string FieldType(int Name);
string FieldTypeByPos(int I);
string GetFieldValue(string Name);
string GetFieldValueByPos(int I);
int SetFieldValue(string Name);

intFieldValueByPos(int I);

in ADOLib.mqh

there are methods:

GetFieldValue

GetFieldValueByPos

after successful opening of the table "SELECT * FROM NameTable"

set to the right record with

int is_succ=MoveFirst();

and if successful, read:

string FieldVal=";

if(is_succ=1)

FieldVal=GetFieldValue("NameField");

or read by the numeric handler of the field:

int hbdFld=0;

if(is_succ=1)

FieldVal=GetFieldValueByPos(hndFld);

Execute SQL from Metatrader Constructors and destructors Integers

Александр 2010.05.20 11:59 #79

the MoveFirst() method which sets to the FIRST entry,

the ones you want are either overridden by MoveNext(),

and the ones you don't want are either searched and/or filtered.

see. Find(),Filter() or WHERE in SELECT....

Александр 2010.05.20 12:02 #80

and also the GetFieldValueXXXX data reading methods convert field values to

string type, so if necessary the

to the required type

How to access the database from MQL4 , ORACL , MSSQL, MySQL - page 8