diff --git a/app/crawler/savers/postgres.js b/app/crawler/savers/postgres.js
index 8c1553f..8e31f9d 100644
--- a/app/crawler/savers/postgres.js
+++ b/app/crawler/savers/postgres.js
@@ -14,9 +14,16 @@ class PostgresSaver {
     const savedRecords = await bulkUpsertRealEstates(results);
     //Extruding data for price history table
     const resultPrices = savedRecords.map(realEstate => {
+      //Null values canot be recognized by ignore duplicates in sequalize
+      //Value price = 0 indicates 'cijena na upit'
+      const priceTmp =
+        realEstate.dataValues.price === null ? 0 : realEstate.dataValues.price;
+
       return {
         realEstateId: realEstate.dataValues.id,
-        price: realEstate.dataValues.price
+        price: priceTmp,
+        createdAt: realEstate.dataValues.createdAt,
+        updatedAt: realEstate.dataValues.updatedAt
       };
     });
     const savedPrices = await bulkUpsertPriceHistory(resultPrices);
diff --git a/app/helpers/db/priceHistory.js b/app/helpers/db/priceHistory.js
index 9d62be8..3e8f69e 100644
--- a/app/helpers/db/priceHistory.js
+++ b/app/helpers/db/priceHistory.js
@@ -7,7 +7,8 @@ const bulkUpsertPriceHistory = async priceHistoryData => {
     const order = [["realEstateId", "desc"]];
 
     return await db.PriceHistory.bulkCreate(priceHistoryData, {
-      order
+      order,
+      ignoreDuplicates: true
     });
   } catch (e) {
     console.log("Error bulk upserting priceHistory : ", e);
diff --git a/app/migrations/20200121094500-add-constraint-priceHistory.js b/app/migrations/20200121094500-add-constraint-priceHistory.js
new file mode 100644
index 0000000..45c83c3
--- /dev/null
+++ b/app/migrations/20200121094500-add-constraint-priceHistory.js
@@ -0,0 +1,10 @@
+"use strict";
+module.exports = {
+  up: (queryInterface, Sequelize) =>
+    queryInterface.addConstraint("PriceHistory", ["realEstateId", "price"], {
+      type: "unique",
+      name: "uniquePriceRealEstate"
+    }),
+  down: queryInterface =>
+    queryInterface.removeConstraint("PriceHistory", "uniquePriceRealEstate")
+};
diff --git a/app/models/priceHistory.js b/app/models/priceHistory.js
index 560a4fa..495be53 100644
--- a/app/models/priceHistory.js
+++ b/app/models/priceHistory.js
@@ -1,29 +1,35 @@
 "use strict";
 
 module.exports = (sequalize, DataTypes) => {
-  const PriceHistory = sequalize.define("PriceHistory", {
-    id: {
-      type: DataTypes.BIGINT,
-      autoIncrement: true,
-      primaryKey: true,
-      allowNull: false
-    },
-    realEstateId: {
-      type: DataTypes.BIGINT,
-      allowNull: false,
-      unique: "uniquePriceRealEstate",
-      references: {
-        model: "RealEstates",
-        key: "id"
+  const PriceHistory = sequalize.define(
+    "PriceHistory",
+    {
+      id: {
+        type: DataTypes.BIGINT,
+        autoIncrement: true,
+        primaryKey: true,
+        allowNull: false
       },
-      onUpdate: "CASCADE",
-      onDelete: "SET NULL"
+      realEstateId: {
+        type: DataTypes.BIGINT,
+        allowNull: false,
+        unique: "uniquePriceRealEstate",
+        references: {
+          model: "RealEstates",
+          key: "id"
+        },
+        onUpdate: "CASCADE",
+        onDelete: "SET NULL"
+      },
+      price: {
+        type: DataTypes.REAL,
+        unique: "uniquePriceRealEstate"
+      }
     },
-    price: {
-      type: DataTypes.REAL,
-      unique: "uniquePriceRealEstate"
+    {
+      freezeTableName: true
     }
-  });
+  );
 
   PriceHistory.associate = models => {
     PriceHistory.hasMany(models.RealEstate, {
diff --git a/app/seeders/20200121150443-initial-price-history.js b/app/seeders/20200121150443-initial-price-history.js
new file mode 100644
index 0000000..9d2f5b0
--- /dev/null
+++ b/app/seeders/20200121150443-initial-price-history.js
@@ -0,0 +1,19 @@
+"use strict";
+
+module.exports = {
+  up: (queryInterface, Sequelize) => {
+    // ??
+    const realEstateInitialData = await queryInterface.Sequelize.findall ();
+    const priceHistoryInitialData = realEstateInitialData.map ();
+    
+    return queryInterface.bulkInsert(
+      "PriceHistory",
+      priceHistoryInitialData,
+      {}
+    );
+  },
+
+  down: (queryInterface, Sequelize) => {
+    return queryInterface.bulkDelete("PriceHistory", null, {});
+  }
+};