Podcast Beta
Questions and Answers
What is the primary key constraint used to define in a table, as shown in Q2?
The primary key constraint is used to uniquely identify each record in a table, in this case, the ECODE column.
What is the purpose of the FOREIGN KEY constraint in the table design shown in Q3?
The FOREIGN KEY constraint is used to establish a relationship between two tables, in this case, the DEPT table and the ECODE table.
What is the purpose of the CHECK constraint in the table design shown in Q4 and Q5?
The CHECK constraint is used to limit the value range that can be placed in a column, in this case, the SALARY column and the CITY column.
What is the purpose of modifying the EMP table to add a new column GENDER, as shown in Q6?
Signup and view all the answers
What is the purpose of using the WHERE clause in the UPDATE statement, as shown in Q9?
Signup and view all the answers
What is the purpose of using the LIKE operator with the UPPER function, as shown in Q11?
Signup and view all the answers
What is the purpose of the query in Q18?
Signup and view all the answers
What is the benefit of using the UNION operator in Q20?
Signup and view all the answers
What is the primary key in the Salesman-Detail table?
Signup and view all the answers
What is the purpose of normalization in database design?
Signup and view all the answers
What is the purpose of the MGR_CODE column in the employee table?
Signup and view all the answers
What is the benefit of using the QTY column in the Salesman-Detail table?
Signup and view all the answers
Study Notes
SQL Table Design and Queries
- SQL statement for table creation includes fields like ECODE, ENAME, ADDRESS, SALARY, PHONE, and AGE with respective data types (NUMBER and VARCHAR2).
- A PRIMARY KEY constraint is added to ECODE to ensure unique identification of records in the table.
Foreign Key Implementation
- Design includes a table with PRIMARY KEY (ECODE) and FOREIGN KEY (DEPTNO).
- Structure: EMP table includes fields: ECODE (PK), ENAME, ADDRESS, AGE, DEPTNO (FK) linked to DEPT table.
- DEPT table has its own PRIMARY KEY (DEPTNO), along with DNAME and DLOCATION.
Check Constraints for Data Integrity
- Salary can be constrained to a range of 1000-5000 and limited to specific city values (Rishikesh, Dehradun, Haridwar).
- Another table (EMP) includes compulsory fields with respective constraints for ECODE, ENAME, ADDRESS, and AGE.
Table Modification and Record Manipulation
- EMP table can be modified to include a new column for GENDER.
- Various SQL operations include inserting, updating, and deleting records based on specific conditions (e.g., age, name).
- Deletion operations are case insensitive for names and allow for filtering conditions.
Querying Employee Data
- Queries to retrieve lists of employees based on age (e.g., >50, between 30 to 50) and specific name patterns (e.g., ends with 'R').
- Capability to filter employees by address proximity, department, and salary thresholds (greater or less than 15000).
- UNION operator is utilized to combine results from different criteria (e.g., employees in the computer department or earning over 15000).
Designing Manager Relationship Table
- Creation of a table for employees including their manager's details with necessary attributes for ECODE, NAME, ADDRESS, SALARY, and related manager information.
Salesman Detail Compilation
- Structure includes fields for salesmen information and sales tracking with necessary identifiers like SCODE (PK), SNAME, ADDRESS, and sales transaction details.
- Queries for identifying salesmen with highest sales quantities and total sales amounts.
Normalization of Employee Data
- Provided employee dataset needs normalization to eliminate redundancy, aligning fields properly (e.g., JOB_CODE, STATE_CODE, HOME_STATE) across a well-organized schema.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your skills in creating SQL statements for designing tables with primary and foreign keys, and constraints. This quiz covers various scenarios, including designing tables with primary keys, foreign keys, and check constraints.
