title: retrieve data from database into html using flask
body: <p>I want to display data from a PostgreSQL database in an HTML web page on clicking a search button. When I search with values of a row I am getting values of all the rows. I want to display the values of that particular row and not that of all the rows.</p>
  
  <pre><code>@app.route("/search", methods=['GET','POST'])
  def search():
      if request.method == "POST":  
          course = request.form['book']
          # input_id = request.POST["book"]
          # cur = conn.cursor()
          try:
              cursor.execute("select course_id,course_name  from course where course_id &lt; 5;",(course))
          except Exception,e:
              conn.rollback()
          else:
              conn.commit()
          data = cursor.fetchall()
          # if len(data) == 0 and course == 5:
          #     cursor.execute("select course_id,course_name from course;",(course_id,))
          #     conn.commit()
          #     data = cursor.query.all()
  
          return render_template('search.html', data=data)
      return render_template('search.html')
  if __name__ == "__main__":
   from flask_sqlalchemy import get_debug_queries
   app.run(debug=True)
  
      enter code here
  
  </code></pre>