CREATE TABLE table_38843 ("Name" TEXT, "Type" TEXT, "Entered service" TEXT, "Water depth" TEXT, "Location" TEXT)

Where is Transocean Richardson, a semi entered into service in 1988?
SELECT "Location" FROM table_38843 WHERE "Type" = 'semi' AND "Entered service" = '1988' AND "Name" = 'transocean richardson'
SELECT "Location" FROM "table_38843" WHERE "Entered service" = '1988' AND "Name" = 'transocean richardson' AND "Type" = 'semi'