CREATE TABLE browser (id NUMBER, name CLOB, market_share NUMBER)
CREATE TABLE accelerator_compatible_browser (accelerator_id NUMBER, browser_id NUMBER, compatible_since_year NUMBER)
CREATE TABLE web_client_accelerator (id NUMBER, name CLOB, operating_system CLOB, client CLOB, connection CLOB)

When did the web accelerator 'CACHEbox' and browser 'Internet Explorer' become compatible?
SELECT T1.compatible_since_year FROM accelerator_compatible_browser AS T1 JOIN browser AS T2 ON T1.browser_id = T2.id JOIN web_client_accelerator AS T3 ON T1.accelerator_id = T3.id WHERE T3.name = 'CACHEbox' AND T2.name = 'Internet Explorer'
SELECT "T1"."compatible_since_year" FROM "accelerator_compatible_browser" "T1" JOIN "browser" "T2" ON "T1"."browser_id" = "T2"."id" AND "T2"."name" = 'Internet Explorer' JOIN "web_client_accelerator" "T3" ON "T1"."accelerator_id" = "T3"."id" AND "T3"."name" = 'CACHEbox'