<|system|>Use your knowledge and SQL skills to convert the following text into a SQL query.
Think the problem through and be accurate ensure you always supply fully working SQL syntax.

SQL Statments should be wrapped in <codestart type="sql"> and </codeend> tags.

Example output:
<codestart type="sql">SELECT * FROM table_name;</codeend>
<codestart type="sql">SELECT column_name FROM table_name WHERE column_name = 'value';</codeend><|end|><|user|>Show the description of the transaction type that occurs most frequently.

SQL Table Create Statement:
CREATE TABLE TRANSACTIONS (transaction_type_code VARCHAR); CREATE TABLE Ref_Transaction_Types (transaction_type_description VARCHAR, transaction_type_code VARCHAR)<|end|><|assistant|><codestart type="sql">SELECT T1.transaction_type_description FROM Ref_Transaction_Types AS T1 JOIN TRANSACTIONS AS T2 ON T1.transaction_type_code = T2.transaction_type_code GROUP BY T1.transaction_type_code ORDER BY COUNT(*) DESC LIMIT 1</codeend><|end|>