Modeling and Accessing Relational Data | Oracle Magazine
Project Employee project manager (FK) employee manager (FK) Manager manager It is interesting to note that the relational database modeling tool, ERWin. That sounds like a many to many relationship where you need a bridge table. You would store everyone in an employee table with an ID and. Part 2 in a series on the basics of the relational database and SQL. that you can use for viewing and managing the data in an Oracle Database instance via SQL. Figure 1: EMPLOYEE and DEPARTMENT tables with a 1:M relationship.
To simplify the example, you only copy five columns from the original table. Then, you query the HumanResources. EmployeeDemo table to review how the data is structured in a table without using the hierarchyid data type.HOW TO GET EMPLOYEES AND THEIR MANAGER NAMES BY USING SELF JOIN-- SQL Server Tutorials
Copy the Employee table In a Query Editor window, run the following code to copy the table structure and data from the Employee table into a new table named EmployeeDemo. Since the original table already uses hierarchyid, this query essentially flattens the hierarchy to retrieve the manager of the employee. In subsequent parts of this lesson we will be reconstructing this hierarchy.
EmployeeDemo' is not null drop table HumanResources. Employee emp ; GO Examine the structure and data of the EmployeeDemo table This new EmployeeDemo table represents a typical table in an existing database that you might want to migrate to a new structure. The results continue for a total of rows.
For instance, all seven of the direct reports of MgrID 1 ken0 are listed adjacent to each other.
Database Design - Recursive associations
Although not impossible, it is much more difficult to group all those who eventually report to MgrID 1. Populate a Table with Existing Hierarchical Data This task creates a new table and populates it with the data in the EmployeeDemo table.
This task has the following steps: Create a new table that contains a hierarchyid column. However, you will retain those columns.
Role of Managers in Employee Relationship
This is because existing applications might refer to those columns, and also to help you understand the data after the transfer. The table definition specifies that OrgNode is the primary key, which requires the column to contain unique values.
The clustered index on the OrgNode column will store the date in OrgNode sequence. Create a temporary table that is used to track how many employees report directly to each manager. Populate the new table by using data from the EmployeeDemo table. Note how the Num column contains sequential numbers for each manager.
Use the GetRoot and ToString methods to concatenate the Num values into the hierarchyid format, and then update the OrgNode column with the resultant hierarchical values: Review the data in the NewOrg table by executing the following code, which contains two representations of the OrgNode column: The team leader or the manager plays an important role in promoting healthy relation at workplace: It is essential that the supervisor assigns challenging tasks to his team member as per his specialization and interest.
The individual should have interest in the work; otherwise he would treat it as a burden and unnecessarily crib about things.
Design pattern: recursive associations
It is important that the team leader understands his team members well. Try to find out their interests and what all they expect from the organization. While developing their KRAs it is always better if the team leader calls everyone and invites suggestions from them. Let them decide what best they can perform. This way the employees would never blame each other or their superior later as they themselves have decided on the roles and responsibilities.
Encourage them to willingly accept the challenge.
- Modeling and Accessing Relational Data
- Lesson 1: Converting a Table to a Hierarchical Structure
- Recursive Hierarchies (Master Data Services)
They would strive hard for a better output without fighting and finding faults in each other. A team leader should be a role model to his team members. He should treat each and every individual as one and avoid partialities at work. Do not give anyone a special treatment just because he drops your son to school every day or says a yes to whatever you say.
Appreciate if someone has done exceptionally well but do make sure to correct him if he is wrong somewhere. The team leader should not be rude or harsh to anyone.
There is a correct way for everything and one should not insult any team member. It is strictly unethical. Sit with him and make him realize his mistakes. He would definitely look up to you in future. The superior must not act pricy and should always be accessible to his employees.
The individuals must have the liberty to walk up to their immediate bosses in case of a doubt and clear things. The hierarchy should not be too complicated as it leads to confusions and disputes among employees.
The manager must ensure that all important communication takes place on an open forum for everyone to get a common picture. Problems arise when communication is done on a one to one basis.