Table: race_results_23
Columns: year
entrant
chassis
engine
points

Question: What is the average Year when there was a cosworth straight-4 engine, and the Entrant was ron harris / team lotus?
SQL: SELECT AVG("year") FROM race_results_23 WHERE "engine" = 'cosworth straight-4' AND "entrant" = 'ron harris / team lotus'

Question: What is the name of the Entrant that has a Chassis of lotus 25
SQL: SELECT "entrant" FROM race_results_23 WHERE "chassis" = 'lotus 25'

Question: What was the engine when the chassis was a porsche 718??
SQL: SELECT "engine" FROM race_results_23 WHERE "chassis" = 'porsche 718'

Question: What is the number of points when there was a BMW 269 F2 chassis earlier than 1969?
SQL: SELECT COUNT("points") FROM race_results_23 WHERE "chassis" = 'bmw 269 f2' AND "year" < 1969

Question: What engine was in the lotus 44 f2 Chassis?
SQL: SELECT "engine" FROM race_results_23 WHERE "chassis" = 'lotus 44 f2'

Question: What year was there a lotus 25 Chassis?
SQL: SELECT "year" FROM race_results_23 WHERE "chassis" = 'lotus 25'