Who wrote the episodes directed by David Straiton?
CREATE TABLE table_21312845_1 (written_by VARCHAR, directed_by VARCHAR)
SELECT written_by FROM table_21312845_1 WHERE directed_by = "David Straiton"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_21312845_1 (written_by VARCHAR, directed_by VARCHAR) Question: Who wrote the episodes directed by David Straiton? [/INST] SELECT written_by FROM table_21312845_1 WHERE directed_by = "David Straiton" </s>