SQL Exercises: Employees whose department location is Toronto
SQL SUBQUERY: Exercise-16 with Solution
From the following table, write a SQL query to find those employees whose department is located at ‘Toronto’. Return first name, last name, employee ID, job ID.
Sample table: employees+-------------+-------------+-------------+----------+--------------------+------------+------------+----------+----------------+------------+---------------+ | EMPLOYEE_ID | FIRST_NAME | LAST_NAME | EMAIL | PHONE_NUMBER | HIRE_DATE | JOB_ID | SALARY | COMMISSION_PCT | MANAGER_ID | DEPARTMENT_ID | +-------------+-------------+-------------+----------+--------------------+------------+------------+----------+----------------+------------+---------------+ | 100 | Steven | King | SKING | 515.123.4567 | 2003-06-17 | AD_PRES | 24000.00 | 0.00 | 0 | 90 | | 101 | Neena | Kochhar | NKOCHHAR | 515.123.4568 | 2005-09-21 | AD_VP | 17000.00 | 0.00 | 100 | 90 | | 102 | Lex | De Haan | LDEHAAN | 515.123.4569 | 2001-01-13 | AD_VP | 17000.00 | 0.00 | 100 | 90 | | 103 | Alexander | Hunold | AHUNOLD | 590.423.4567 | 2006-01-03 | IT_PROG | 9000.00 | 0.00 | 102 | 60 | | 104 | Bruce | Ernst | BERNST | 590.423.4568 | 2007-05-21 | IT_PROG | 6000.00 | 0.00 | 103 | 60 | | 105 | David | Austin | DAUSTIN | 590.423.4569 | 2005-06-25 | IT_PROG | 4800.00 | 0.00 | 103 | 60 | | 106 | Valli | Pataballa | VPATABAL | 590.423.4560 | 2006-02-05 | IT_PROG | 4800.00 | 0.00 | 103 | 60 | | 107 | Diana | Lorentz | DLORENTZ | 590.423.5567 | 2007-02-07 | IT_PROG | 4200.00 | 0.00 | 103 | 60 | | 108 | Nancy | Greenberg | NGREENBE | 515.124.4569 | 2002-08-17 | FI_MGR | 12008.00 | 0.00 | 101 | 100 | | 109 | Daniel | Faviet | DFAVIET | 515.124.4169 | 2002-08-16 | FI_ACCOUNT | 9000.00 | 0.00 | 108 | 100 | | 110 | John | Chen | JCHEN | 515.124.4269 | 2005-09-28 | FI_ACCOUNT | 8200.00 | 0.00 | 108 | 100 | | 111 | Ismael | Sciarra | ISCIARRA | 515.124.4369 | 2005-09-30 | FI_ACCOUNT | 7700.00 | 0.00 | 108 | 100 | | 112 | Jose Manuel | Urman | JMURMAN | 515.124.4469 | 2006-03-07 | FI_ACCOUNT | 7800.00 | 0.00 | 108 | 100 | | 113 | Luis | Popp | LPOPP | 515.124.4567 | 2007-12-07 | FI_ACCOUNT | 6900.00 | 0.00 | 108 | 100 | | 114 | Den | Raphaely | DRAPHEAL | 515.127.4561 | 2002-12-07 | PU_MAN | 11000.00 | 0.00 | 100 | 30 | | 115 | Alexander | Khoo | AKHOO | 515.127.4562 | 2003-05-18 | PU_CLERK | 3100.00 | 0.00 | 114 | 30 | | 116 | Shelli | Baida | SBAIDA | 515.127.4563 | 2005-12-24 | PU_CLERK | 2900.00 | 0.00 | 114 | 30 | | 117 | Sigal | Tobias | STOBIAS | 515.127.4564 | 2005-07-24 | PU_CLERK | 2800.00 | 0.00 | 114 | 30 | | 118 | Guy | Himuro | GHIMURO | 515.127.4565 | 2006-11-15 | PU_CLERK | 2600.00 | 0.00 | 114 | 30 | | 119 | Karen | Colmenares | KCOLMENA | 515.127.4566 | 2007-08-10 | PU_CLERK | 2500.00 | 0.00 | 114 | 30 | | 120 | Matthew | Weiss | MWEISS | 650.123.1234 | 2004-07-18 | ST_MAN | 8000.00 | 0.00 | 100 | 50 | | 121 | Adam | Fripp | AFRIPP | 650.123.2234 | 2005-04-10 | ST_MAN | 8200.00 | 0.00 | 100 | 50 | | 122 | Payam | Kaufling | PKAUFLIN | 650.123.3234 | 2003-05-01 | ST_MAN | 7900.00 | 0.00 | 100 | 50 | | 123 | Shanta | Vollman | SVOLLMAN | 650.123.4234 | 2005-10-10 | ST_MAN | 6500.00 | 0.00 | 100 | 50 | | 124 | Kevin | Mourgos | KMOURGOS | 650.123.5234 | 2007-11-16 | ST_MAN | 5800.00 | 0.00 | 100 | 50 | | 125 | Julia | Nayer | JNAYER | 650.124.1214 | 2005-07-16 | ST_CLERK | 3200.00 | 0.00 | 120 | 50 | | 126 | Irene | Mikkilineni | IMIKKILI | 650.124.1224 | 2006-09-28 | ST_CLERK | 2700.00 | 0.00 | 120 | 50 | | 127 | James | Landry | JLANDRY | 650.124.1334 | 2007-01-14 | ST_CLERK | 2400.00 | 0.00 | 120 | 50 | | 128 | Steven | Markle | SMARKLE | 650.124.1434 | 2008-03-08 | ST_CLERK | 2200.00 | 0.00 | 120 | 50 | | 129 | Laura | Bissot | LBISSOT | 650.124.5234 | 2005-08-20 | ST_CLERK | 3300.00 | 0.00 | 121 | 50 | | 130 | Mozhe | Atkinson | MATKINSO | 650.124.6234 | 2005-10-30 | ST_CLERK | 2800.00 | 0.00 | 121 | 50 | | 131 | James | Marlow | JAMRLOW | 650.124.7234 | 2005-02-16 | ST_CLERK | 2500.00 | 0.00 | 121 | 50 | | 132 | TJ | Olson | TJOLSON | 650.124.8234 | 2007-04-10 | ST_CLERK | 2100.00 | 0.00 | 121 | 50 | | 133 | Jason | Mallin | JMALLIN | 650.127.1934 | 2004-06-14 | ST_CLERK | 3300.00 | 0.00 | 122 | 50 | | 134 | Michael | Rogers | MROGERS | 650.127.1834 | 2006-08-26 | ST_CLERK | 2900.00 | 0.00 | 122 | 50 | | 135 | Ki | Gee | KGEE | 650.127.1734 | 2007-12-12 | ST_CLERK | 2400.00 | 0.00 | 122 | 50 | | 136 | Hazel | Philtanker | HPHILTAN | 650.127.1634 | 2008-02-06 | ST_CLERK | 2200.00 | 0.00 | 122 | 50 | | 137 | Renske | Ladwig | RLADWIG | 650.121.1234 | 2003-07-14 | ST_CLERK | 3600.00 | 0.00 | 123 | 50 | | 138 | Stephen | Stiles | SSTILES | 650.121.2034 | 2005-10-26 | ST_CLERK | 3200.00 | 0.00 | 123 | 50 | | 139 | John | Seo | JSEO | 650.121.2019 | 2006-02-12 | ST_CLERK | 2700.00 | 0.00 | 123 | 50 | | 140 | Joshua | Patel | JPATEL | 650.121.1834 | 2006-04-06 | ST_CLERK | 2500.00 | 0.00 | 123 | 50 | | 141 | Trenna | Rajs | TRAJS | 650.121.8009 | 2003-10-17 | ST_CLERK | 3500.00 | 0.00 | 124 | 50 | | 142 | Curtis | Davies | CDAVIES | 650.121.2994 | 2005-01-29 | ST_CLERK | 3100.00 | 0.00 | 124 | 50 | | 143 | Randall | Matos | RMATOS | 650.121.2874 | 2006-03-15 | ST_CLERK | 2600.00 | 0.00 | 124 | 50 | | 144 | Peter | Vargas | PVARGAS | 650.121.2004 | 2006-07-09 | ST_CLERK | 2500.00 | 0.00 | 124 | 50 | | 145 | John | Russell | JRUSSEL | 011.44.1344.429268 | 2004-10-01 | SA_MAN | 14000.00 | 0.40 | 100 | 80 | | 146 | Karen | Partners | KPARTNER | 011.44.1344.467268 | 2005-01-05 | SA_MAN | 13500.00 | 0.30 | 100 | 80 | | 147 | Alberto | Errazuriz | AERRAZUR | 011.44.1344.429278 | 2005-03-10 | SA_MAN | 12000.00 | 0.30 | 100 | 80 | | 148 | Gerald | Cambrault | GCAMBRAU | 011.44.1344.619268 | 2007-10-15 | SA_MAN | 11000.00 | 0.30 | 100 | 80 | | 149 | Eleni | Zlotkey | EZLOTKEY | 011.44.1344.429018 | 2008-01-29 | SA_MAN | 10500.00 | 0.20 | 100 | 80 | | 150 | Peter | Tucker | PTUCKER | 011.44.1344.129268 | 2005-01-30 | SA_REP | 10000.00 | 0.30 | 145 | 80 | | 151 | David | Bernstein | DBERNSTE | 011.44.1344.345268 | 2005-03-24 | SA_REP | 9500.00 | 0.25 | 145 | 80 | | 152 | Peter | Hall | PHALL | 011.44.1344.478968 | 2005-08-20 | SA_REP | 9000.00 | 0.25 | 145 | 80 | | 153 | Christopher | Olsen | COLSEN | 011.44.1344.498718 | 2006-03-30 | SA_REP | 8000.00 | 0.20 | 145 | 80 | | 154 | Nanette | Cambrault | NCAMBRAU | 011.44.1344.987668 | 2006-12-09 | SA_REP | 7500.00 | 0.20 | 145 | 80 | | 155 | Oliver | Tuvault | OTUVAULT | 011.44.1344.486508 | 2007-11-23 | SA_REP | 7000.00 | 0.15 | 145 | 80 | | 156 | Janette | King | JKING | 011.44.1345.429268 | 2004-01-30 | SA_REP | 10000.00 | 0.35 | 146 | 80 | | 157 | Patrick | Sully | PSULLY | 011.44.1345.929268 | 2004-03-04 | SA_REP | 9500.00 | 0.35 | 146 | 80 | | 158 | Allan | McEwen | AMCEWEN | 011.44.1345.829268 | 2004-08-01 | SA_REP | 9000.00 | 0.35 | 146 | 80 | | 159 | Lindsey | Smith | LSMITH | 011.44.1345.729268 | 2005-03-10 | SA_REP | 8000.00 | 0.30 | 146 | 80 | | 160 | Louise | Doran | LDORAN | 011.44.1345.629268 | 2005-12-15 | SA_REP | 7500.00 | 0.30 | 146 | 80 | | 161 | Sarath | Sewall | SSEWALL | 011.44.1345.529268 | 2006-11-03 | SA_REP | 7000.00 | 0.25 | 146 | 80 | | 162 | Clara | Vishney | CVISHNEY | 011.44.1346.129268 | 2005-11-11 | SA_REP | 10500.00 | 0.25 | 147 | 80 | | 163 | Danielle | Greene | DGREENE | 011.44.1346.229268 | 2007-03-19 | SA_REP | 9500.00 | 0.15 | 147 | 80 | | 164 | Mattea | Marvins | MMARVINS | 011.44.1346.329268 | 2008-01-24 | SA_REP | 7200.00 | 0.10 | 147 | 80 | | 165 | David | Lee | DLEE | 011.44.1346.529268 | 2008-02-23 | SA_REP | 6800.00 | 0.10 | 147 | 80 | | 166 | Sundar | Ande | SANDE | 011.44.1346.629268 | 2008-03-24 | SA_REP | 6400.00 | 0.10 | 147 | 80 | | 167 | Amit | Banda | ABANDA | 011.44.1346.729268 | 2008-04-21 | SA_REP | 6200.00 | 0.10 | 147 | 80 | | 168 | Lisa | Ozer | LOZER | 011.44.1343.929268 | 2005-03-11 | SA_REP | 11500.00 | 0.25 | 148 | 80 | | 169 | Harrison | Bloom | HBLOOM | 011.44.1343.829268 | 2006-03-23 | SA_REP | 10000.00 | 0.20 | 148 | 80 | | 170 | Tayler | Fox | TFOX | 011.44.1343.729268 | 2006-01-24 | SA_REP | 9600.00 | 0.20 | 148 | 80 | | 171 | William | Smith | WSMITH | 011.44.1343.629268 | 2007-02-23 | SA_REP | 7400.00 | 0.15 | 148 | 80 | | 172 | Elizabeth | Bates | EBATES | 011.44.1343.529268 | 2007-03-24 | SA_REP | 7300.00 | 0.15 | 148 | 80 | | 173 | Sundita | Kumar | SKUMAR | 011.44.1343.329268 | 2008-04-21 | SA_REP | 6100.00 | 0.10 | 148 | 80 | | 174 | Ellen | Abel | EABEL | 011.44.1644.429267 | 2004-05-11 | SA_REP | 11000.00 | 0.30 | 149 | 80 | | 175 | Alyssa | Hutton | AHUTTON | 011.44.1644.429266 | 2005-03-19 | SA_REP | 8800.00 | 0.25 | 149 | 80 | | 176 | Jonathon | Taylor | JTAYLOR | 011.44.1644.429265 | 2006-03-24 | SA_REP | 8600.00 | 0.20 | 149 | 80 | | 177 | Jack | Livingston | JLIVINGS | 011.44.1644.429264 | 2006-04-23 | SA_REP | 8400.00 | 0.20 | 149 | 80 | | 178 | Kimberely | Grant | KGRANT | 011.44.1644.429263 | 2007-05-24 | SA_REP | 7000.00 | 0.15 | 149 | 0 | | 179 | Charles | Johnson | CJOHNSON | 011.44.1644.429262 | 2008-01-04 | SA_REP | 6200.00 | 0.10 | 149 | 80 | | 180 | Winston | Taylor | WTAYLOR | 650.507.9876 | 2006-01-24 | SH_CLERK | 3200.00 | 0.00 | 120 | 50 | | 181 | Jean | Fleaur | JFLEAUR | 650.507.9877 | 2006-02-23 | SH_CLERK | 3100.00 | 0.00 | 120 | 50 | | 182 | Martha | Sullivan | MSULLIVA | 650.507.9878 | 2007-06-21 | SH_CLERK | 2500.00 | 0.00 | 120 | 50 | | 183 | Girard | Geoni | GGEONI | 650.507.9879 | 2008-02-03 | SH_CLERK | 2800.00 | 0.00 | 120 | 50 | | 184 | Nandita | Sarchand | NSARCHAN | 650.509.1876 | 2004-01-27 | SH_CLERK | 4200.00 | 0.00 | 121 | 50 | | 185 | Alexis | Bull | ABULL | 650.509.2876 | 2005-02-20 | SH_CLERK | 4100.00 | 0.00 | 121 | 50 | | 186 | Julia | Dellinger | JDELLING | 650.509.3876 | 2006-06-24 | SH_CLERK | 3400.00 | 0.00 | 121 | 50 | | 187 | Anthony | Cabrio | ACABRIO | 650.509.4876 | 2007-02-07 | SH_CLERK | 3000.00 | 0.00 | 121 | 50 | | 188 | Kelly | Chung | KCHUNG | 650.505.1876 | 2005-06-14 | SH_CLERK | 3800.00 | 0.00 | 122 | 50 | | 189 | Jennifer | Dilly | JDILLY | 650.505.2876 | 2005-08-13 | SH_CLERK | 3600.00 | 0.00 | 122 | 50 | | 190 | Timothy | Gates | TGATES | 650.505.3876 | 2006-07-11 | SH_CLERK | 2900.00 | 0.00 | 122 | 50 | | 191 | Randall | Perkins | RPERKINS | 650.505.4876 | 2007-12-19 | SH_CLERK | 2500.00 | 0.00 | 122 | 50 | | 192 | Sarah | Bell | SBELL | 650.501.1876 | 2004-02-04 | SH_CLERK | 4000.00 | 0.00 | 123 | 50 | | 193 | Britney | Everett | BEVERETT | 650.501.2876 | 2005-03-03 | SH_CLERK | 3900.00 | 0.00 | 123 | 50 | | 194 | Samuel | McCain | SMCCAIN | 650.501.3876 | 2006-07-01 | SH_CLERK | 3200.00 | 0.00 | 123 | 50 | | 195 | Vance | Jones | VJONES | 650.501.4876 | 2007-03-17 | SH_CLERK | 2800.00 | 0.00 | 123 | 50 | | 196 | Alana | Walsh | AWALSH | 650.507.9811 | 2006-04-24 | SH_CLERK | 3100.00 | 0.00 | 124 | 50 | | 197 | Kevin | Feeney | KFEENEY | 650.507.9822 | 2006-05-23 | SH_CLERK | 3000.00 | 0.00 | 124 | 50 | | 198 | Donald | OConnell | DOCONNEL | 650.507.9833 | 2007-06-21 | SH_CLERK | 2600.00 | 0.00 | 124 | 50 | | 199 | Douglas | Grant | DGRANT | 650.507.9844 | 2008-01-13 | SH_CLERK | 2600.00 | 0.00 | 124 | 50 | | 200 | Jennifer | Whalen | JWHALEN | 515.123.4444 | 2003-09-17 | AD_ASST | 4400.00 | 0.00 | 101 | 10 | | 201 | Michael | Hartstein | MHARTSTE | 515.123.5555 | 2004-02-17 | MK_MAN | 13000.00 | 0.00 | 100 | 20 | | 202 | Pat | Fay | PFAY | 603.123.6666 | 2005-08-17 | MK_REP | 6000.00 | 0.00 | 201 | 20 | | 203 | Susan | Mavris | SMAVRIS | 515.123.7777 | 2002-06-07 | HR_REP | 6500.00 | 0.00 | 101 | 40 | | 204 | Hermann | Baer | HBAER | 515.123.8888 | 2002-06-07 | PR_REP | 10000.00 | 0.00 | 101 | 70 | | 205 | Shelley | Higgins | SHIGGINS | 515.123.8080 | 2002-06-07 | AC_MGR | 12008.00 | 0.00 | 101 | 110 | | 206 | William | Gietz | WGIETZ | 515.123.8181 | 2002-06-07 | AC_ACCOUNT | 8300.00 | 0.00 | 205 | 110 | +-------------+-------------+-------------+----------+--------------------+------------+------------+----------+----------------+------------+---------------+Sample table: departments
+---------------+----------------------+------------+-------------+ | DEPARTMENT_ID | DEPARTMENT_NAME | MANAGER_ID | LOCATION_ID | +---------------+----------------------+------------+-------------+ | 10 | Administration | 200 | 1700 | | 20 | Marketing | 201 | 1800 | | 30 | Purchasing | 114 | 1700 | | 40 | Human Resources | 203 | 2400 | | 50 | Shipping | 121 | 1500 | | 60 | IT | 103 | 1400 | | 70 | Public Relations | 204 | 2700 | | 80 | Sales | 145 | 2500 | | 90 | Executive | 100 | 1700 | | 100 | Finance | 108 | 1700 | | 110 | Accounting | 205 | 1700 | | 120 | Treasury | 0 | 1700 | | 130 | Corporate Tax | 0 | 1700 | | 140 | Control And Credit | 0 | 1700 | | 150 | Shareholder Services | 0 | 1700 | | 160 | Benefits | 0 | 1700 | | 170 | Manufacturing | 0 | 1700 | | 180 | Construction | 0 | 1700 | | 190 | Contracting | 0 | 1700 | | 200 | Operations | 0 | 1700 | | 210 | IT Support | 0 | 1700 | | 220 | NOC | 0 | 1700 | | 230 | IT Helpdesk | 0 | 1700 | | 240 | Government Sales | 0 | 1700 | | 250 | Retail Sales | 0 | 1700 | | 260 | Recruiting | 0 | 1700 | | 270 | Payroll | 0 | 1700 | +---------------+----------------------+------------+-------------+Sample table: locations
+-------------+------------------------------------------+-------------+---------------------+-------------------+------------+ | LOCATION_ID | STREET_ADDRESS | POSTAL_CODE | CITY | STATE_PROVINCE | COUNTRY_ID | +-------------+------------------------------------------+-------------+---------------------+-------------------+------------+ | 1000 | 1297 Via Cola di Rie | 989 | Roma | | IT | | 1100 | 93091 Calle della Testa | 10934 | Venice | | IT | | 1200 | 2017 Shinjuku-ku | 1689 | Tokyo | Tokyo Prefecture | JP | | 1300 | 9450 Kamiya-cho | 6823 | Hiroshima | | JP | | 1400 | 2014 Jabberwocky Rd | 26192 | Southlake | Texas | US | | 1500 | 2011 Interiors Blvd | 99236 | South San Francisco | California | US | | 1600 | 2007 Zagora St | 50090 | South Brunswick | New Jersey | US | | 1700 | 2004 Charade Rd | 98199 | Seattle | Washington | US | | 1800 | 147 Spadina Ave | M5V 2L7 | Toronto | Ontario | CA | | 1900 | 6092 Boxwood St | YSW 9T2 | Whitehorse | Yukon | CA | | 2000 | 40-5-12 Laogianggen | 190518 | Beijing | | CN | | 2100 | 1298 Vileparle (E) | 490231 | Bombay | Maharashtra | IN | | 2200 | 12-98 Victoria Street | 2901 | Sydney | New South Wales | AU | | 2300 | 198 Clementi North | 540198 | Singapore | | SG | | 2400 | 8204 Arthur St | | London | | UK | | 2500 | Magdalen Centre, The Oxford Science Park | OX9 9ZB | Oxford | Oxford | UK | | 2600 | 9702 Chester Road | 9629850293 | Stretford | Manchester | UK | | 2700 | Schwanthalerstr. 7031 | 80925 | Munich | Bavaria | DE | | 2800 | Rua Frei Caneca 1360 | 01307-002 | Sao Paulo | Sao Paulo | BR | | 2900 | 20 Rue des Corps-Saints | 1730 | Geneva | Geneve | CH | | 3000 | Murtenstrasse 921 | 3095 | Bern | BE | CH | | 3100 | Pieter Breughelstraat 837 | 3029SK | Utrecht | Utrecht | NL | | 3200 | Mariano Escobedo 9991 | 11932 | Mexico City | Distrito Federal, | MX | +-------------+------------------------------------------+-------------+---------------------+-------------------+------------+
Sample Solution:
-- Selecting specific columns (first_name, last_name, employee_id, job_id) from the 'employees' table
SELECT first_name, last_name, employee_id, job_id
-- Filtering rows based on the condition that the 'department_id' matches the result of a nested subquery
FROM employees
-- Subquery to find the 'department_id' where the location's city is 'Toronto'
WHERE department_id =
(SELECT department_id
FROM departments
-- Subquery to find the 'location_id' where the city is 'Toronto' in the 'locations' table
WHERE location_id =
(SELECT location_id
FROM locations
WHERE city ='Toronto')
);
Sample Output:
first_name last_name employee_id job_id Michael Hartstein 201 MK_MAN Pat Fay 202 MK_REP
Code Explanation:
The said query in SQL that retrieves the first name, last name, employee ID, and job ID of all employees who work in a department located in Toronto. The query first retrieves the location ID of all locations in the city of Toronto by using a subquery in the "WHERE" clause.
A subquery is then used to retrieve the department IDs of all of the departments located at that particular location using an additional query.
Finally, it retrieves the relevant employee information by matching the department ID with the departments in the 'employees' table.
Visual Presentation:
Alternative Statements:
Using JOIN:
SELECT e.first_name, e.last_name, e.employee_id, e.job_id
FROM employees e
JOIN departments d ON e.department_id = d.department_id
JOIN locations l ON d.location_id = l.location_id
WHERE l.city = 'Toronto';
Using EXISTS:
SELECT first_name, last_name, employee_id, job_id
FROM employees e
WHERE EXISTS (
SELECT 1
FROM departments d
JOIN locations l ON d.location_id = l.location_id
WHERE d.department_id = e.department_id
AND l.city = 'Toronto'
);
Using IN:
SELECT first_name, last_name, employee_id, job_id
FROM employees
WHERE department_id IN (
SELECT department_id
FROM departments
WHERE location_id IN (
SELECT location_id
FROM locations
WHERE city = 'Toronto'
)
);
Practice Online
Query Visualization:
Duration:
Rows:
Cost:
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