如何检查PyMySQL中是否存在数据库

Question

我正在尝试检查Python中是否存在数据库。我发现可以使用以下sql语句完成此操作：Uncaught TypeError: old.remove is not a function 但是，在尝试执行它后，出现以下错误：

cur.execute(f'SHOW DATABASES LIKE {event["db_name"]}')

Answer 1

您在语句中遗漏了撇号，可以在%语句中使用LIKE来匹配更多结果，请尝试以下操作：

cur.execute(f"SHOW DATABASES LIKE '%{event["db_name"]}%;'")

有关LIKE运算符的更多信息：

LIKE 'a%'   Finds any values that start with "a"
LIKE '%a'   Finds any values that end with "a"
LIKE '%or%' Finds any values that have "or" in any position
LIKE '_r%'  Finds any values that have "r" in the second position
LIKE 'a__%' Finds any values that start with "a" and are at least 3 characters in length
LIKE 'a%o'  Finds any values that start with "a" and ends with "o"

Answer 2

发现错误是由于以下事实引起的：我需要用引号将数据库名称引起来，以便以下SQL语句起作用：cur.execute(f'SHOW DATABASES LIKE "{event["db_name"]}"')