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Task 33:
Retrieve the EMP_NO and SALARY of employees from the EMPLOYEE table, categorize the records into three equal groups (BUCKETS) based on salary values. Output result in 3 columns: EMP_NO, SALARY and BUCKET, ensure that the results are sorted in ascending order by salary.

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Use Firebird syntax to write your answer. Descriptions of tables are provided at the bottom of the screen.

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Employee Database: table structure and overview

The Employee database (Firebird) is a sample dataset used to learn SQL and explore Firebird DBMS capabilities.

This page describes table structure, key columns, and relationships for practical SQL querying.

The Employee database contains 9 main tables.

ER diagram of the Employee database showing table relationships ER diagram of the Employee database

List of tables

COUNTRY - countries table.
  • COUNTRYName of the country
  • CURRENCYCurrency used in the country
COUNTRY CURRENCY
USA Dollar
JOB - company's staff schedule.
  • JOB_CODEJob code
  • JOB_GRADEJob grade
  • JOB_COUNTRYCountry associated with the job
  • JOB_TITLEJob title
  • MIN_SALARYMinimum salary for the job
  • MAX_SALARYMaximum salary for the job
  • JOB_REQUIREMENTJob requirements
  • LANGUAGE_REQLanguage requirements
JOB_CODE JOB_GRADE JOB_COUNTRY JOB_TITLE MIN_SALARY MAX_SALARY JOB_REQUIREMENT LANGUAGE_REQ
CEO 1 USA Chief Executive Officer 130000.00 250000.00 No specific requirements. [null]
  • FOREIGN KEY (JOB_COUNTRY) REFERENCES COUNTRY(COUNTRY)
DEPARTMENT - company divisions.
  • DEPT_NODepartment number
  • DEPARTMENTDepartment name
  • HEAD_DEPTHead department (can be null)
  • MNGR_NOManager number
  • BUDGETDepartment budget
  • LOCATIONDepartment location
  • PHONE_NOPhone number for the department
DEPT_NO DEPARTMENT HEAD_DEPT MNGR_NO BUDGET LOCATION PHONE_NO
000 Corporate Office [null] 105 1000000.00 Monterey (408) 555-1234
  • FOREIGN KEY (HEAD_DEPT) REFERENCES DEPARTMENT(DEPT_NO)
EMPLOYEE - list of employees.
  • EMP_NOEmployee number
  • FIRST_NAMEFirst name of the employee
  • LAST_NAMELast name of the employee
  • PHONE_EXTPhone extension for the employee
  • HIRE_DATEDate of employee's hire
  • DEPT_NODepartment number
  • JOB_CODEJob code for the employee
  • JOB_GRADEJob grade for the employee
  • JOB_COUNTRYCountry associated with the employee's job
  • SALARYSalary of the employee
  • FULL_NAMEFull name of the employee
EMP_NO FIRST_NAME LAST_NAME PHONE_EXT HIRE_DATE DEPT_NO JOB_CODE JOB_GRADE JOB_COUNTRY SALARY FULL_NAME
2 Robert Nelson 250 1988-12-28 00:00:00 600 VP 2 USA 105900.00 Nelson, Robert
  • FOREIGN KEY (DEPT_NO) REFERENCES DEPARTMENT(DEPT_NO)
  • FOREIGN KEY (JOB_CODE) REFERENCES JOB(JOB_CODE)
PROJECT - list of projects.
  • PROJ_IDProject ID
  • PROJ_NAMEProject name
  • PROJ_DESCProject description
  • TEAM_LEADERTeam leader for the project
  • PRODUCTProduct associated with the project
PROJ_ID PROJ_NAME PROJ_DESC TEAM_LEADER PRODUCT
VBASE Video Database Development of a video database management system for managing video distribution on demand. 45 software
  • FOREIGN KEY (TEAM_LEADER) REFERENCES EMPLOYEE(EMP_NO)
EMPLOYEE_PROJECT - employee-project mapping.
  • EMP_NOEmployee number
  • PROJ_IDProject ID
EMP_NO PROJ_ID
144 DGPII
  • FOREIGN KEY (EMP_NO) REFERENCES EMPLOYEE(EMP_NO)
  • FOREIGN KEY (PROJ_ID) REFERENCES PROJECT(PROJ_ID)
PROJ_DEPT_BUDGET - project budgets.
  • FISCAL_YEARFiscal year
  • PROJ_IDProject ID
  • DEPT_NODepartment number
  • QUART_HEAD_CNTQuarter headcount (can be null)
  • PROJECTED_BUDGETProjected budget for the fiscal year
FISCAL_YEAR PROJ_ID DEPT_NO QUART_HEAD_CNT PROJECTED_BUDGET
1994 GUIDE 100 [null] 200000.00
  • FOREIGN KEY (PROJ_ID) REFERENCES PROJECT(PROJ_ID)
  • FOREIGN KEY (DEPT_NO) REFERENCES DEPARTMENT(DEPT_NO)
SALARY_HISTORY - history of employee salary changes.
  • EMP_NOEmployee number
  • CHANGE_DATEDate of salary change
  • UPDATER_IDUpdater ID
  • OLD_SALARYPrevious salary
  • PERCENT_CHANGEPercentage change in salary
  • NEW_SALARYNew salary after the change
EMP_NO CHANGE_DATE UPDATER_ID OLD_SALARY PERCENT_CHANGE NEW_SALARY
28 1992-12-15 00:00:00 admin2 20000.00 10.000000 22000.000000
  • FOREIGN KEY (EMP_NO) REFERENCES EMPLOYEE(EMP_NO)
CUSTOMER - company clients.
  • CUST_NOCustomer number
  • CUSTOMERCustomer name
  • CONTACT_FIRSTFirst name of the contact person
  • CONTACT_LASTLast name of the contact person
  • PHONE_NOPhone number for the customer
  • ADDRESS_LINE1 Address line 1
  • ADDRESS_LINE2Address line 2 (can be null)
  • CITYCity of the customer
  • STATE_PROVINCEState or province of the customer
  • COUNTRYCountry of the customer
  • POSTAL_CODEPostal code of the customer
  • ON_HOLDOn hold status (can be null)
CUST_NO CUSTOMER CONTACT_FIRST CONTACT_LAST PHONE_NO ADDRESS_LINE1 ADDRESS_LINE2 CITY STATE_PROVINCE COUNTRY POSTAL_CODE ON_HOLD
1001 Signature Design Dale J. Little (619) 530-2710 15500 Pacific Heights Blvd. [null] San Diego CA USA 92121 [null]
  • FOREIGN KEY (COUNTRY) REFERENCES COUNTRY(COUNTRY)
SALES - list of sales.
  • PO_NUMBERPurchase order number
  • CUST_NOCustomer number associated with the order
  • SALES_REPSales representative number
  • ORDER_STATUSOrder status
  • ORDER_DATEDate of the order
  • SHIP_DATEDate of shipment
  • DATE_NEEDEDDate needed (can be null)
  • PAIDPayment status
  • QTY_ORDEREDQuantity ordered
  • TOTAL_VALUETotal value of the order
  • DISCOUNTDiscount applied
  • ITEM_TYPEType of item in the order
  • AGEDAged value
PO_NUMBER CUST_NO SALES_REP ORDER_STATUS ORDER_DATE SHIP_DATE DATE_NEEDED PAID QTY_ORDERED TOTAL_VALUE DISCOUNT ITEM_TYPE AGED
V91E0210 1004 11 shipped 1991-03-04 00:00:00 1991-03-05 00:00:00 [null] y 10 5000.00 0.100000 hardware 1.000000000
  • FOREIGN KEY (CUST_NO) REFERENCES CUSTOMER(CUST_NO)
  • FOREIGN KEY (SALES_REP) REFERENCES EMPLOYEE(EMP_NO)

Below is a list of this DB views:

PHONE_LIST - employee phone list view.
  • EMP_NOEmployee number
  • FIRST_NAMEFirst name of the employee
  • LAST_NAMELast name of the employee
  • PHONE_EXTPhone extension for the employee
  • LOCATIONDepartment location
  • PHONE_NODepartment phone number
EMP_NO FIRST_NAME LAST_NAME PHONE_EXT LOCATION PHONE_NO
2 Robert Nelson 250 Monterey (408) 555-1234
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