--Use the NOT keyword to select all records where City is NOT "Berlin"
SELECT * FROM Customers
WHERE NOT City = ‘Berlin‘;
--通配符 _
--Select all records where the first letter of the City is an "a" or a "c" or an "s".
SELECT * FROM Customers
WHERE City LIKE '[acs]%';
--Select all records where the first letter of the City is NOT an "a" or a "c" or an "f".
SELECT * FROM Customers
WHERE City LIKE '[!acf]%';
--Use the TRUNCATE statement to delete all data inside a table. 只删除数据,不删除表本身
TRUNCATE TABLE Persons;
--Add a column of type DATE called Birthday.
ALTER TABLE Persons
ADD Birthday DATE;
--Delete the column Birthday from the Persons table.
ALTER TABLE Persons
DROP COLUMN Birthday;
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