如何在SQLAlchemy中漂亮地格式化SQL查询的打印？

Question

我正在使用SQLAlchemy动态生成PL/SQL，使用compile并设置dialect和compile_kwargs参数（例如，使用str(ins.compile(dialect=oracle.dialect(), compile_kwargs={'literal_binds': True}))），这很好，只是输出没有用最漂亮的SQL语句格式化。

例如，我的一个输出如下所示：

INSERT INTO my_table (a, b, c) SELECT my_table2.d, bar.e, bar.f 
FROM my_table2 JOIN (SELECT my_table3.e AS e, max(my_table3.f) AS f, count(my_table3.g) AS g 
FROM my_table3 
WHERE my_table3.h = 'foo' GROUP BY my_table3.e 
HAVING count(my_table3.g) = 1) bar ON my_table2.g = bar.g

相反，我希望这样打印出来：

INSERT INTO my _table (a, b c)
SELECT my_table2.d, bar.e, bar.f
FROM my_table2 JOIN (
    SELECT my_table3.e, max(my_table3.f), count(my_table3.g)
    FROM my_table3
    WHERE my_table3.h = 'foo'
    GROUP BY my_table3.e
    HAVING count(my_table3.g) = 1
) bar ON my_table2.g = bar.g

如何让SQLAlchemy漂亮地打印SQL语句？

---

要复制：

from sqlalchemy import table, column, String, Numeric, func, select
from sqlalchemy.dialects import oracle
my_table = table('my_table', column('a', String), column('b', String), column('c', String))
my_table2 = table('my_table2', column('d', String), column('g', String))
my_table3 = table('my_table3', column('d', String), column('e', String), column('f', Numeric), column('g', String), column('h', String))

inner_sel = select([my_table3.c.e, func.max(my_table3.c.f).label('f'), func.count(my_table3.c.g).label('g')]).where(my_table3.c.h=='foo').group_by(my_table3.c.e).having(func.count(my_table3.c.g)==1).alias('bar')


outer_sel = select([my_table2.c.d, inner_sel.c.e, inner_sel.c.f]).select_from(my_table2.join(inner_sel, my_table2.c.g==inner_sel.c.g))

ins = my_table.insert().from_select([my_table.c.a, my_table.c.b, my_table.c.c], outer_sel)

print ins.compile(dialect=oracle.dialect(), compile_kwargs={'literal_binds': True})