Create a query that uses both a wildcard character and an aggregate function.

CREATE TABLE HOUSE (HouseAddress CHAR(50), HouseOwner CHAR(30), Insurance CHAR(40));

INSERT INTO HOUSE VALUES ('285 Westport Rd', 'John', 'Yes'), ('213 Longboard Ln', 'Josh', 'Yes'), ('321 Surf Rd', 'Marisol', 'No');

CREATE TABLE HEATINGUNIT (HeatingUnitID INT, UnitName CHAR(30), UnitType CHAR(40), Manufactory CHAR(40), DateOfBuilt Date, Capacity INT, HouseAddress CHAR(50)); INSERT INTO HEATINGUNIT VALUES (4, 'Large', 'Solar', 'GE', NULL, 3000, '213 Longboard Lne'), (3, 'Small', 'Electric', 'GE', NULL, 6000, '213 Longboard Ln'), (1, 'Small', 'Gas', 'LG', NULL, 2000, '285 Westport Rd'), (2, 'Large', 'Solar', 'GE', NULL, 3500, '285 Westport Rd'), (6, 'Medium', 'Hybrid', 'LG', NULL, 3000, '321 Surf Rd'), (5, 'Medium', 'Hybrid', 'LG', NULL, 2000, '321 Surf Rd');

CREATE TABLE TECHNICIAN (EmployeeNumber INT, EmployeeName CHAR(30), Title CHAR(40), YearHired INT); INSERT INTO TECHNICIAN VALUES (1, 'John', 'Tech1', 2004), (2, 'Jordan', 'Tech2', 2006), (3, 'JohnAllen', 'Supervisor', 2015);

CREATE TABLE SERVICE (HeatingUnitID INT, ServiceType CHAR(40), Date Date, Time TimeSTAMP, EmployeeNumber INT);

INSERT INTO SERVICE VALUES (1, 'Repair', NULL, NULL, 1), (2, 'Repair', NULL, NULL, 2), (3, 'Maintenance', NULL, NULL, 2), (4, 'Maintenance', NULL, NULL, 2);