diff --git a/src/db-scripts/init.sql b/src/db-scripts/init.sql
index 6b49bd5..5e6d7be 100644
--- a/src/db-scripts/init.sql
+++ b/src/db-scripts/init.sql
@@ -20,13 +20,14 @@ CREATE TABLE IF NOT EXISTS refreshtokens (
 
 CREATE TABLE IF NOT EXISTS roles (
     id SERIAL PRIMARY KEY,
-    name VARCHAR(50),
+    name VARCHAR(50) NOT NULL,
     description VARCHAR(250)
 );
 
 CREATE TABLE IF NOT EXISTS users_roles (
     role_id INT NOT NULL,
     user_id INT NOT NULL,
+    PRIMARY KEY(role_id, user_id),
     CONSTRAINT fk_role FOREIGN KEY(role_id) REFERENCES roles(id),
     CONSTRAINT fk_user FOREIGN KEY(user_id) REFERENCES users(id)
 );
@@ -49,6 +50,7 @@ CREATE TABLE IF NOT EXISTS addresses (
 CREATE TABLE IF NOT EXISTS users_addresses (
     user_id INT NOT NULL,
     address_id INT NOT NULL,
+    PRIMARY KEY(user_id, address_id),
     CONSTRAINT fk_user FOREIGN KEY(user_id) REFERENCES users(id),
     CONSTRAINT fk_address FOREIGN KEY(address_id) REFERENCES addresses(id)
 );
@@ -61,6 +63,7 @@ CREATE TABLE IF NOT EXISTS customer_types (
 CREATE TABLE IF NOT EXISTS customers (
     user_id INT NOT NULL,
     type_id INT NOT NULL,
+    PRIMARY KEY(user_id, type_id),
     CONSTRAINT fk_user FOREIGN KEY(user_id) REFERENCES users(id),
     CONSTRAINT fk_type FOREIGN KEY(type_id) REFERENCES customer_types(id)
 );
@@ -85,12 +88,10 @@ CREATE TABLE IF NOT EXISTS estimations (
     id SERIAL PRIMARY KEY,
     service_type INT NOT NULL,
     building_type SMALLINT NOT NULL,
-    address_id INT NOT NULL,
     family_size SMALLINT NOT NULL,
-    equipments VARCHAR(50) NOT NULL,
+    equipments INT[] NOT NULL,
     past_consumption REAL NOT NULL,
-    estimated_consumption REAL NOT NULL,
-    CONSTRAINT fk_address FOREIGN KEY(address_id) REFERENCES addresses(id)
+    estimated_consumption REAL NOT NULL
 );
 
 /*https://www.globalpetrolprices.com/Belgium/electricity_prices/#hl183*/
@@ -98,7 +99,7 @@ CREATE TABLE IF NOT EXISTS estimations (
 CREATE TABLE IF NOT EXISTS tariffs (
     id SERIAL PRIMARY KEY,
     customer_type_id INT NOT NULL,
-    service_type VARCHAR(50) NOT NULL,
+    service_type INT NOT NULL,
     value REAL NOT NULL,
     CONSTRAINT fk_customer_type FOREIGN KEY(customer_type_id) REFERENCES customer_types(id)
 );
@@ -111,8 +112,8 @@ CREATE TABLE IF NOT EXISTS contract_statuses (
 
 CREATE TABLE IF NOT EXISTS contracts (
     id SERIAL PRIMARY KEY,
-    start_date DATE NOT NULL,
-    end_date DATE NOT NULL,
+    start_date DATE,
+    end_date DATE,
     tariff_id INT NOT NULL,
     estimation_id INT NOT NULL,
     address_id INT NOT NULL,
@@ -126,6 +127,7 @@ CREATE TABLE IF NOT EXISTS contracts (
 CREATE TABLE IF NOT EXISTS customers_contracts (
     user_id INT NOT NULL,
     contract_id INT NOT NULL,
+    PRIMARY KEY(user_id, contract_id),
     CONSTRAINT fk_user FOREIGN KEY(user_id) REFERENCES users(id),
     CONSTRAINT fk_contract FOREIGN KEY(contract_id) REFERENCES contracts(id)
 );
@@ -147,7 +149,7 @@ CREATE TABLE IF NOT EXISTS plannings (
 CREATE TABLE IF NOT EXISTS meters (
     id SERIAL PRIMARY KEY,
     meter_type VARCHAR(50) NOT NULL,
-    physical_id INT NOT NULL
+    physical_id INT
 );
 
 CREATE TABLE IF NOT EXISTS indexed_values (
@@ -169,6 +171,7 @@ CREATE TABLE IF NOT EXISTS consumptions (
 CREATE TABLE IF NOT EXISTS contracts_meters (
     contract_id INT NOT NULL,
     meter_id INT NOT NULL,
+    PRIMARY KEY(contract_id, meter_id),
     CONSTRAINT fk_contract FOREIGN KEY(contract_id) REFERENCES contracts(id),
     CONSTRAINT fk_meter FOREIGN KEY(meter_id) REFERENCES meters(id)
 );
@@ -205,6 +208,7 @@ CREATE TABLE IF NOT EXISTS invoices (
 CREATE TABLE IF NOT EXISTS invoices_statuses (
     invoice_id INT NOT NULL,
     status_id INT NOT NULL,
+    PRIMARY KEY(invoice_id, status_id),
     CONSTRAINT fk_invoice FOREIGN KEY(invoice_id) REFERENCES invoices(id),
     CONSTRAINT fk_status FOREIGN KEY(status_id) REFERENCES invoice_statuses(id)
 );
diff --git a/src/db-scripts/static_tables.sql b/src/db-scripts/static_tables.sql
index 2e0b933..730931b 100644
--- a/src/db-scripts/static_tables.sql
+++ b/src/db-scripts/static_tables.sql
@@ -1,22 +1,22 @@
-INSERT INTO contracts_status (name,description) 
+INSERT INTO contract_statuses (name,description) 
 VALUES
     ('Not Validated', 'When a contract is created but the meter values are not read yet and the contracted has not started.'),
     ('Active', 'Meters are read and the contract has started'),
     ('Expired', 'End date reached and not renewed' );
 
-INSERT INTO customers_types (description) 
+INSERT INTO customer_types (description) 
 VALUES
     ('Private'),
     ('Company');
 
 
-INSERT INTO invoices_types (name,description) 
+INSERT INTO invoice_types (name,description) 
 VALUES
     ('Advance Payment', 'Invoicing each month a fixed amount based on the estimated consumption'),
     ('Debit Note','End of year invoice to be paid by customer'),
-    ('Credit Note', "End of year invoice in customer's favour");
+    ('Credit Note', 'End of year invoice in customer''s favour');
 
-INSERT INTO plannings_statuses (description) 
+INSERT INTO planning_statuses (description) 
 VALUES
     ('Scheduled'),
     ('Done');
@@ -33,15 +33,16 @@ VALUES
     ('hr_manager', 'hr_manager'),
     ('admin', 'admin');
 
-INSERT INTO statuses_for_invoices (description) 
+INSERT INTO invoice_statuses (description) 
 VALUES
     ('Due'),
     ('Late'),
     ('Paid');
 
-INSERT INTO tariffs(customer_type, service_type, value)
+INSERT INTO tariffs(customer_type_id, service_type, value)
 VALUES
-    (1,'Electricity',0.291),
-    (2,'Electricity',0.106),
-    (1,'Gas',0.068),
-    (2,'Gas',0.046);
+    (1,1,0.291),
+    (2,1,0.106),
+    (1,2,0.068),
+    (2,2,0.046);
+-- Electricity = 1, Gas = 2
\ No newline at end of file