有什么办法能让这看起来好一点吗?
conn.exec 'select attr1, attr2, attr3, attr4, attr5, attr6, attr7 ' +
'from table1, table2, table3, etc, etc, etc, etc, etc, ' +
'where etc etc etc etc etc etc etc etc etc etc etc etc etc'
比如,有没有办法暗示串联?
有什么办法能让这看起来好一点吗?
conn.exec 'select attr1, attr2, attr3, attr4, attr5, attr6, attr7 ' +
'from table1, table2, table3, etc, etc, etc, etc, etc, ' +
'where etc etc etc etc etc etc etc etc etc etc etc etc etc'
比如,有没有办法暗示串联?
当前回答
其他选项:
#multi line string
multiline_string = <<EOM
This is a very long string
that contains interpolation
like #{4 + 5} \n\n
EOM
puts multiline_string
#another option for multiline string
message = <<-EOF
asdfasdfsador #{2+2} this month.
asdfadsfasdfadsfad.
EOF
puts message
其他回答
是的,如果你不介意额外的换行被插入:
conn.exec 'select attr1, attr2, attr3, attr4, attr5, attr6, attr7
from table1, table2, table3, etc, etc, etc, etc, etc,
where etc etc etc etc etc etc etc etc etc etc etc etc etc'
你也可以使用heredoc:
conn.exec <<-eos
select attr1, attr2, attr3, attr4, attr5, attr6, attr7
from table1, table2, table3, etc, etc, etc, etc, etc,
where etc etc etc etc etc etc etc etc etc etc etc etc etc
eos
conn.exec = <<eos
select attr1, attr2, attr3, attr4, attr5, attr6, attr7
from table1, table2, table3, etc, etc, etc, etc, etc,
where etc etc etc etc etc etc etc etc etc etc etc etc etc
eos
最近,随着Ruby 2.3的新特性,新的弯弯曲曲的HEREDOC将允许您以一种非常好的方式编写多行字符串,并且只需要进行最小的更改,因此,将它与.squish(如果您正在使用rails)结合使用将使您以一种非常好的方式编写多行字符串! 在只使用ruby的情况下,您可以执行<<~SQL.split。Join(" "),几乎相同
[1] pry(main)> <<~SQL.squish
[1] pry(main)* select attr1, attr2, attr3, attr4, attr5, attr6, attr7
[1] pry(main)* from table1, table2, table3, etc, etc, etc, etc, etc,
[1] pry(main)* where etc etc etc etc etc etc etc etc etc etc etc etc etc
[1] pry(main)* SQL
=> "select attr1, attr2, attr3, attr4, attr5, attr6, attr7 from table1, table2, table3, etc, etc, etc, etc, etc, where etc etc etc etc etc etc etc etc etc etc etc etc etc"
裁判:https://infinum.co/the-capsized-eight/multiline-strings-ruby-2-3-0-the-squiggly-heredoc
在ruby 2.0中,你现在可以只使用%
例如:
SQL = %{
SELECT user, name
FROM users
WHERE users.id = #{var}
LIMIT #{var2}
}
如果你不介意额外的空格和换行,你可以使用
conn.exec %w{select attr1, attr2, attr3, attr4, attr5, attr6, attr7
from table1, table2, table3, etc, etc, etc, etc, etc,
where etc etc etc etc etc etc etc etc etc etc etc etc etc} * ' '
(使用%W表示插值字符串)