Posts

Showing posts with the label Not Null Constraint
  ❖Communication practices: Principle 1 Listen: •Try to focus on the speaker‘s words, rather than formulating your response to those words. •Ask for clarification if something is unclear, but avoid constant interruptions. •Never become contentious in your words or actions (e.g., rolling your eyes or shaking your head) as a person is talking. Principle 2 Prepare before you communicate: •Spend the time to understand the problem before you meet with others. If necessary, perform some research to understand business domain. •If you have responsibility for conducting a meeting, prepare an agenda in advance of the meeting. Principle 3 someone should facilitate the activity: •Every communication meeting should have a leader (a facilitator) 1)To keep the conversation moving in a productive direction, 2)To mediate any conflict that does occur, and 3)To ensure that other principles are followed. Principle 4 Face-to-face communication is best: •It usually works better when some other represen...

What is Not Null Constraint

Not Null Constraint Database many have same mandatory attributes  . Ex-mobile no, email Id, Address is mandatory when new user for the registration, These attributes in a database are not allowed null in values  . In a student table, student first name and last name are mandatory are middle name many be optional  . syntax-Create table table name (column name datatype (size) not null . Create table student (first name varchar (255) not null, middle name, varchar (255), last name varchar (255) not null); .In database management system inserting null values can prevent by using not null constraint, same attributes in database are not allowed to contain null values that null value are unknown or missing same in attribute value in above example student first name and last name is not null there fore first name column and last name column required