user: Question: On what date did congressman Joseph Tydings enter take his seat?
Columns: ['Rank', 'Senator', 'Date of birth', 'Entered Senate', 'Left Senate', 'State served', 'Party', 'Time since entry']
Types: ['real', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'Birch Bayh', 'January 22, 1928', 'January 3, 1963', 'January 3, 1981', 'Indiana', 'Democrat', '51years, 29days']
SQL:

assistant: SELECT "Entered Senate" FROM "Table" WHERE "Senator" = 'Joseph Tydings';