diff --git a/.vscode/settings.json b/.vscode/settings.json
index 5ecea1e..90ab211 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -4,6 +4,17 @@
         "vector": "cpp",
         "deque": "cpp",
         "ostream": "cpp",
-        "future": "cpp"
+        "future": "cpp",
+        "optional": "cpp",
+        "array": "cpp",
+        "string_view": "cpp",
+        "initializer_list": "cpp",
+        "utility": "cpp",
+        "mutex": "cpp",
+        "iostream": "cpp",
+        "*.tcc": "cpp",
+        "fstream": "cpp",
+        "new": "cpp",
+        "thread": "cpp"
     }
 }
\ No newline at end of file
diff --git a/lib/mysql.hpp b/lib/mysql.hpp
index 9b3ca03..ee61078 100644
--- a/lib/mysql.hpp
+++ b/lib/mysql.hpp
@@ -51,6 +51,8 @@ class sqlQA {
     sqlQA& set(const string _column_value_pairs);
     sqlQA& deleteFrom(const string _table);
 
+    void print(bool withDetail = false);
+
     // answer methods
 
     private:
@@ -62,49 +64,29 @@ class mySQL {
     mutex io;
     MySQL_Driver *drv;
     // Connection *con;
-    vector<Connection*> con;
+    // vector<Connection*> con;
+    vector<pair<mutex*, Connection*>> con;
     string path, username, password, db;
     bool isPersistent;
     uint numOfCon;
     uint reconTrys = 3;
     
     mySQL(const string _path, const string _username, const string _password, const string _db, const bool _isPersistent = false, const uint _numOfCon = 1);
-    bool open(const string _db = "", const int con_idx = -1);
-    bool connect(const int con_idx = -1);
+    bool open(const string _db = "");
+    bool connect();
     bool disconnect();
     void reconnectTrys(const uint _trys);
     void exec(sqlQA &sql_qa);
-    void getColumns(const string _table, vector<string> &_columns);
-    ~mySQL();
-};
-
-// class mySQLPool {
-//     public:
-
-//     struct Drop {
-//         mySQL* instance;
-//         bool used = false;
-//     };
-
-//     struct Swimmer {
-//         thread instance;
-//         bool used = false;
-//     };
+    void getColumns(const string _table, vector<string> &_columns, Connection *ptr_con); // privatno
 
-//     mutex io;
-//     uint maxpools = 0;
-//     vector<struct Drop> droplets;
-//     bool fixServer = false;
-//     bool fixScheme = false;
-//     vector<struct Swimmer> swimmers;
+    // ove će biti privatne sigurno
+    bool open_one(Connection *ptr_con);
+    bool connect_one(Connection *ptr_con);
+    bool disconnect_one(Connection *ptr_con);
+    pair<mutex*, Connection*> findFreeCon();
 
-//     mySQLPool(const uint _maxpools);
-//     mySQLPool(const uint _maxpools, const string _path, const string _username, const string _password, const string _db);
-
-//     void exec(sqlQA &sql_qa, const string _db = "");
-
-    
-// };
+    ~mySQL();
+};
 
 
 #endif
\ No newline at end of file
diff --git a/src/mysql.cpp b/src/mysql.cpp
index 7ba1e99..b30de26 100644
--- a/src/mysql.cpp
+++ b/src/mysql.cpp
@@ -59,6 +59,21 @@ sqlQA& sqlQA::deleteFrom(const string _table) {
    return *this;
 }
 
+void sqlQA::print(bool withDetail) {
+   // istražit da se prikaže u tabeli
+   for (auto i : result) {
+         for (auto j: i.second) {
+            cout << i.first << " : " << j << endl;
+         }
+   }
+
+   if (withDetail) {
+      cout << "Is executed: " << (executed ? "true" : "false") << endl;
+      cout << "Update catch: " << updateCatch << endl;
+      cout << "Num of rows: " << num_rows << endl;
+      cout << "Num of columns: " << num_columns << endl;
+   }
+}
 
 void sqlQA::parse_columns(const string _columns) {
    istringstream iss(_columns);
@@ -82,6 +97,8 @@ mySQL::mySQL(const string _path, const string _username, const string _password,
    isPersistent = _numOfCon > 1 ? true : _isPersistent;
    numOfCon = _numOfCon;
 
+   cout << "Num of con: " << numOfCon << endl;
+
    drv = get_mysql_driver_instance();
 
    if (isPersistent) {
@@ -98,56 +115,58 @@ mySQL::mySQL(const string _path, const string _username, const string _password,
 
 }
 
-bool mySQL::open(const string _db, const int con_idx) {
+bool mySQL::open(const string _db) {
    io.lock();
    db = _db.empty() ? db : _db;
    bool status = true; // ako true greška je
 
    for (uint i=0; i<con.size(); i++) {
-      con_idx != -1 ? i = con_idx : i;
       try {
-         con[i]->setSchema(db);
+         con[i].second->setSchema(db);
          status = false;
-         io.unlock();
       }
       catch (const SQLException &error) {
          cout << error.what() << endl;
-         io.unlock();
       }
-      con_idx != -1 ? i = con.size() : i;
+
    }
-   
+
+   io.unlock();
    return status;
 }
 
-bool mySQL::connect(const int con_idx) {
+bool mySQL::connect() {
    io.lock();
-   uint trys = 0;
-   bool status = true;
+   // uint trys = 0;
+   // bool status = true;
+   bool Gstatus = true;
 
    for (uint i=0; i<numOfCon; i++) {
-      con_idx != -1 ? i = con_idx : i;
-      while (reconTrys == 0 ? status : (trys < reconTrys && status)) {
+      uint trys = 0;
+      bool status = true;
+      cout << "Init connection " << i << endl;
+      while (reconTrys == unlimited ? status : (trys < reconTrys && status)) {
+         cout << "Try connect " << trys << endl;
          try {
-            if (con_idx == -1) {
-               con.push_back(drv->connect(path, username, password));
-            }
-            else {
-               con[i] = drv->connect(path, username, password);
-            }
+            con.push_back(make_pair(new mutex, drv->connect(path, username, password)));
+            // con[i].first = new mutex;
+            // con[i].second = drv->connect(path, username, password);
             status = false;
-            io.unlock();
+            Gstatus *= status;
          }
          catch (const SQLException &error) {
             cout << error.what() << endl;
             usleep(reconnectSleep);
-            reconTrys == 0 ? trys : trys++;
-            io.unlock();
-         }
+            reconTrys == unlimited ? trys : trys++;
+         }         
       }
    }
 
-   return status;
+   cout << "Num of pairs " << con.size() << endl;
+
+   io.unlock();
+   // return status;
+   return Gstatus;
 }
 
 bool mySQL::disconnect() {
@@ -155,16 +174,14 @@ bool mySQL::disconnect() {
    bool status = true;
 
    for (uint i=0; i<con.size(); i++) {
-      if (con[i]->isValid() && !con[i]->isClosed()) {
+      if (con[i].second->isValid() && !con[i].second->isClosed()) {
          try {
-            con[i]->close();
+            con[i].second->close();
             status = false;
-            io.unlock();
          } 
          catch (const SQLException &error) {
             cout << error.what() << endl;
             status = true;
-            io.unlock();
          }
       }
 
@@ -173,6 +190,61 @@ bool mySQL::disconnect() {
       }
    }
 
+   io.unlock();
+   return status;
+}
+
+bool mySQL::disconnect_one(Connection *ptr_con) {
+   bool status = true;
+
+   if (ptr_con->isValid() && !ptr_con->isClosed()) {
+      try {
+         ptr_con->close();
+         status = false;
+      } 
+      catch (const SQLException &error) {
+         cout << error.what() << endl;
+         status = true;
+      }
+   }
+
+   else {
+      status = false; // već je zatvorena
+   }
+
+   return status;
+}
+
+bool mySQL::connect_one(Connection *ptr_con) {
+   uint trys = 0;
+   bool status = true;
+
+   while (reconTrys == unlimited ? status : (trys < reconTrys && status)) {
+      try {
+         ptr_con = drv->connect(path, username, password);
+         status = false;
+      }
+      catch (const SQLException &error) {
+         cout << error.what() << endl;
+         usleep(reconnectSleep);
+         reconTrys == unlimited ? trys : trys++;
+      }         
+   }
+
+   return status;
+}
+
+bool mySQL::open_one(Connection *ptr_con) {
+   bool status = true; // ako true greška je
+
+   try {
+      ptr_con->setSchema(db);
+      status = false;
+   }
+   catch (const SQLException &error) {
+      cout << error.what() << endl;
+   }
+
    return status;
 }
 
@@ -188,31 +260,28 @@ void mySQL::reconnectTrys(const uint _trys) {
 
 void mySQL::exec(sqlQA &sql_qa) {
 
-   for (uint i=0; i<con.size(); i++) {
-      if (!isPersistent || !con[i]->isValid() || con[i]->isClosed()) {
-         if (connect(i)) {
-            throw string("[ERROR] Unable to connect database ");
-         }
+   pair<mutex*, Connection*> workCon = findFreeCon(); 
 
-         if (open(i)) {
-            throw string("[ERROR] Unable to open database " + db);
-         }
+   if (!isPersistent || !workCon.second->isValid() || workCon.second->isClosed()) {
+      if (connect_one(workCon.second)) {
+         throw string("[ERROR] Unable to connect database ");
       }
-   }
 
-   // find free connection
+      if (open_one(workCon.second)) {
+         throw string("[ERROR] Unable to open database " + db);
+      }
+   }
 
-   io.lock();
    /**/
    try {
       vector<string> columns = sql_qa.columns;
       
       if (columns.empty() && !sql_qa.table.empty()) {
-         getColumns(sql_qa.table, columns);
+         getColumns(sql_qa.table, columns, workCon.second);
       }
 
       Statement *stmt;
-      stmt = con->createStatement();
+      stmt = workCon.second->createStatement();
 
       if (sql_qa.isSelect) {
          ResultSet *res = stmt->executeQuery(sql_qa.cmd);
@@ -225,6 +294,7 @@ void mySQL::exec(sqlQA &sql_qa) {
             }
          }
 
+         res->close();
          delete res;
          sql_qa.num_columns = columns.size();
          sql_qa.num_rows = num_raw_columns/columns.size();
@@ -239,32 +309,33 @@ void mySQL::exec(sqlQA &sql_qa) {
          sql_qa.executed = stmt->execute(sql_qa.cmd);
       }
 
+      stmt->close();
       delete stmt;
-      io.unlock();
    }
    catch (const SQLException &error) {
       cout << error.what() << endl;
       sql_qa.executed = false;
-      io.unlock();
    }
    catch (const string error) {
+      workCon.first->unlock();
       throw error;
-      io.unlock();
    }
 
    /**/
 
    if (!isPersistent) {
-      if(disconnect()) {
+      if(disconnect_one(workCon.second)) {
          throw string("[ERROR] Unable to close database ");
       }
    }
 
+   workCon.first->unlock();
+
 }
 
-void mySQL::getColumns(const string _table, vector<string> &_columns) {
+void mySQL::getColumns(const string _table, vector<string> &_columns, Connection *ptr_con) {
    Statement *stmt;
-   stmt = con->createStatement();
+   stmt = ptr_con->createStatement();
    
    ResultSet *columnsRes = stmt->executeQuery("SHOW COLUMNS from " + _table);
 
@@ -272,59 +343,32 @@ void mySQL::getColumns(const string _table, vector<string> &_columns) {
       _columns.push_back(columnsRes->getString("Field"));
    }
 
+   columnsRes->close();
+   stmt->close();
    delete columnsRes;
    delete stmt;
 }
 
+pair<mutex*, Connection*> mySQL::findFreeCon() {
+   io.lock();
+   while (true) {
+      cout << "Tražim konekciju " << endl;
+      for (uint i=0; i<con.size(); i++) {
+         cout << "Pokušavam s " << i << " konekciju" << endl;
+         if (con[i].first->try_lock()) {
+            cout << "Koristim " << i << " konekciju" << endl;
+            io.unlock();
+            return con[i];
+         }
+         // else {
+         //    usleep(1000);
+         // }
+      }
+   }
+}
+
 mySQL::~mySQL() {
    if(disconnect()) {
       throw string("[ERROR] Unable to close database ");
    }
-}
-
-// mySQLPool::mySQLPool(const uint _maxpools) {
-//    maxpools = _maxpools;
-//    fixServer = false;
-//    fixScheme = true;
-// }
-
-// mySQLPool::mySQLPool(const uint _maxpools, const string _path, const string _username, const string _password, const string _db) {
-//    maxpools = _maxpools;
-//    fixServer = true;
-//    fixScheme = !_db.empty();
-//    for (uint i=0; i<maxpools; i++) {
-//       mySQL tmpmysql(_path, _username, _password, _db);
-//       // struct Drop tmpdrop(new mySQL(_path, _username, _password, _db), false);
-//       droplets.push_back({mySQL(_path, _username, _password, _db, true), false});
-//    }
-// }
-
-// void mySQLPool::exec(sqlQA &sql_qa, const string _db) {
-//    if (!fixScheme && _db.empty()) {
-//       throw string("[ERROR] Database is not selected! ");
-//    }
-
-//    for (uint i=0; i<droplets.size(); i++) {
-//       if (droplets[i].used == false) {
-//          droplets[i].used = true;
-
-//          bool isRunned = false;
-
-//          while (!isRunned) {
-//             for (uint i=0; i<swimmers.size(); i++) {
-//                if (swimmers[i].used == false) {
-//                   swimmers[i].used = true;
-//                   swimmers[i].instance = thread([&]() {
-//                      droplets[i].instance->exec(sql_qa);
-//                   });
-//                   swimmers[i].instance.join();
-//                   swimmers[i].used = false;
-//                   isRunned = true;
-//                }
-//             }
-//          }
-//          droplets[i].used = false;
-//       }
-//    }
-
-// }
+}
\ No newline at end of file
diff --git a/test/compile.sh b/test/compile.sh
index 42fa51e..b71c1b3 100644
--- a/test/compile.sh
+++ b/test/compile.sh
@@ -1 +1 @@
-g++ test.cpp ../src/* -o test.o -lmysqlcppconn
\ No newline at end of file
+g++ test.cpp ../src/* -o test.o -lmysqlcppconn -lpthread
\ No newline at end of file
diff --git a/test/test.cpp b/test/test.cpp
index 283e24b..28d1bfa 100644
--- a/test/test.cpp
+++ b/test/test.cpp
@@ -1,53 +1,95 @@
 #include <iostream>
+#include <thread>
+#include <chrono>
 
 #include "../lib/mysql.hpp"
 
 using namespace std;
+using namespace chrono;
 
 int main() {
-
-    mySQL mydb("tcp://192.168.2.10:3306", "dinio", "H€r5elfInd1aH@nds", "dinio", true);
-
     try {
-
-        sqlQA test_qa;
-        // id,user_id,zone_id,domain,record_type,auth_key,last_update,enabled
-        // test_qa.select().from("records").where("enabled = 0").limit(2);
-        // mydb.exec(test_qa);
-
-        // for (auto i : test_qa.result) {
-        //     for (auto j: i.second) {
-        //         cout << i.first << " : " << j << endl;
+        mySQL mydb("tcp://92.240.56.92:3306", "dinio", "H€r5elfInd1aH@nds", "dinio", true, 2);
+
+        auto start = high_resolution_clock::now();
+
+        // thread t1([&](){
+        //     try {
+        //         sqlQA test_qa;
+        //         test_qa.select().from("records").where("enabled = 1");
+        //         mydb.exec(test_qa);
+        //         test_qa.print(true);
+        //     } catch (const string err) {
+        //         cout << err << endl;
         //     }
-        // }
-
-
-        // test_qa.update("records").set("enabled = 1").where("domain = 'bitelex.test'");
-        // mydb.exec(test_qa);
-        // if (test_qa.executed) {
-        //     cout << "Num rows affect " << test_qa.updateCatch << endl;
-        // }
-
-        // cout << "Num rows " << test_qa.num_rows << " num columns " << test_qa.num_columns << " executed " << test_qa.executed << endl;
-
-
-        // test_qa.insertInTo("records", "id,user_id,zone_id,domain,record_type,auth_key,last_update,enabled").values("'5',2,2,'www.bitelex.test','AAAA','jebiga',NULL,1");
-        test_qa.deleteFrom("records").where("record_type = AAAA");
-        // test_qa.update("records").set("enabled = 0").where("record_type = 'AAAA'");
-        cout << test_qa.cmd << endl;
-        mydb.exec(test_qa);
-        cout << "Num rows " << test_qa.num_rows << " num columns " << test_qa.num_columns << " catch " << test_qa.updateCatch <<  " executed " << test_qa.executed << endl;
-
-
-
-    }
-    catch (const SQLException error) {
+        // });
+
+        // thread t2([&](){
+        //     try {
+        //         sqlQA test_qa;
+        //         test_qa.select().from("zones");
+        //         mydb.exec(test_qa);
+        //         test_qa.print(true);
+        //     } catch (const string err) {
+        //         cout << err << endl;
+        //     }
+        // });
+
+        // thread t3([&](){
+        //     try {
+        //         sqlQA test_qa;
+        //         test_qa.select().from("users");
+        //         mydb.exec(test_qa);
+        //         test_qa.print(true);
+        //     } catch (const string err) {
+        //         cout << err << endl;
+        //     }
+        // });
+
+
+        // t1.join();
+        // t2.join();
+        // t3.join();
+
+        // one by one
+        try {
+            sqlQA test_qa;
+            test_qa.select().from("records").where("enabled = 1");
+            mydb.exec(test_qa);
+            test_qa.print(true);
+        } catch (const string err) {
+            cout << err << endl;
+        }
+    
+        try {
+            sqlQA test_qa;
+            test_qa.select().from("users");
+            mydb.exec(test_qa);
+            test_qa.print(true);
+        } catch (const string err) {
+            cout << err << endl;
+        }
+
+        try {
+            sqlQA test_qa;
+            test_qa.select().from("users");
+            mydb.exec(test_qa);
+            test_qa.print(true);
+        } catch (const string err) {
+            cout << err << endl;
+        }
+
+
+        auto end = high_resolution_clock::now();
+        auto duration = duration_cast<microseconds>(end - start);
+        cout << "-------------Izvršilo se za: " << (double)(duration.count() / 1000.0) << endl;
+        
+        
+    } catch (const SQLException error) {
         cout << error.what() << endl;
-    }
-    // catch (const string error) {
-    //     cout << error << endl;
-    // }
-    catch (...) {
+    } catch (const string error) {
+        cout << error << endl;
+    } catch (...) {
         cout << "Jebi ga" << endl;
     }
 
diff --git a/test/test.o b/test/test.o
index f6f4967..9ef803e 100755
Binary files a/test/test.o and b/test/test.o differ