CREATE TABLE volunteers (
    volunteer_id INTEGER PRIMARY KEY,
    contact_id INTEGER NOT NULL,
    experience_years INTEGER NOT NULL,
    FOREIGN KEY (contact_id) REFERENCES contact_details(contact_id)
);
 CREATE TABLE projects (
    project_id INTEGER PRIMARY KEY,
    title VARCHAR(255) NOT NULL,
    organization_id INTEGER NOT NULL,
    start_date DATE NOT NULL,
    end_date DATE NOT NULL,
    budget REAL,
    FOREIGN KEY (organization_id) REFERENCES organizations(organization_id)
);
CREATE TABLE assignments (
    assignment_id INTEGER PRIMARY KEY,
    volunteer_id INTEGER NOT NULL,
    project_id INTEGER NOT NULL,
    assignment_date DATE NOT NULL,
    title VARCHAR(255) NOT NULL,
    status VARCHAR(255),
    FOREIGN KEY (volunteer_id) REFERENCES volunteers(volunteer_id),
    FOREIGN KEY (project_id) REFERENCES projects(project_id)
);
CREATE TABLE contact_details (
    contact_id INTEGER PRIMARY KEY,
    name VARCHAR(255) NOT NULL,
    address VARCHAR(255),
    email VARCHAR(255),
    phone_number VARCHAR(255)
);
 
 CREATE TABLE feedback (
    feedback_id INTEGER PRIMARY KEY,
    project_id INTEGER NOT NULL,
    feedback_text VARCHAR(255),
    FOREIGN KEY (project_id) REFERENCES projects(project_id)
);
CREATE TABLE organizations (
    organization_id INTEGER PRIMARY KEY,
    organization_type VARCHAR(255),
    contact_id INTEGER NOT NULL,
    FOREIGN KEY (contact_id) REFERENCES contact_details(contact_id)
);