when was the marriage when became dauphine is 31 august 1412?
CREATE TABLE table_name_79 (marriage VARCHAR, became_dauphine VARCHAR)
SELECT marriage FROM table_name_79 WHERE became_dauphine = "31 august 1412"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_name_79 (marriage VARCHAR, became_dauphine VARCHAR) Question: when was the marriage when became dauphine is 31 august 1412? [/INST] SELECT marriage FROM table_name_79 WHERE became_dauphine = "31 august 1412" </s>