Test Plan define the testing activity those are perform during testing of the project.Like
1. What is going to be tested (overview)
2. What is the environment.
3. Testing activity
4. Staffing & Training.
5. Testing approach (manual/automation)
7. Db Migration activity (If needed)
Test Strategy define the outline of the testing activity, way of doing the testing for the project.
1. Testing overview.
2. Testing groups
4. Testing Tools
A document describing scope, approach, resources and schedule of intended test activities. It identifies amongst others, test items, the features to be tested, the testing tasks, who will do each task, the degree of tester independence,. The test environment, The test design techniques, the entry and exit criteria to be used and the rationale for their choice and any risks that requires contingency planning. It’s the record of the Test planning process
IEEE 829 Test Plan Template Contains the following :
• Test Plan Identifier
• Test Items
• Features to be tested
• Features not to be tested
• Pass / Fail Criteria
• Suspension and resumption criteria
• Test Deliverables
• Test Tasks
• Environmental Needs
• Staffing and Training Needs
• Risks and Contingencies
A high level description of the test levels to be performed and the testing within those levels for an organization or program (one or more projects)
The implementation of the test strategy for a specific project. It typically includes the decisions made based on the (test) projects goal and risk assessment carried out, starting points regarding the test process, the test design techniques to be applied, exit criteria and test types to be performed
More Ref : Foundations of Software Testing - ISTQB Certification
Test Strategy: Test strategy is a part of test plan,it describes scope of the product/project,
company guidlines or policies,Levels which company follows, Is these levels perform in an sequeence i.e Unit, integration and system,Integration test testing iteration,system testing iteration,How much testing is manual /automated.
Once test strategy is freezed it cant be changed
But test plan can change.
Test Strategy defines timelines on which Test plan works.
Test Plan:Test Plan is document that describes objectives scope,approach and focus of an software testing effort.