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
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
其他回答
conn.exec [
"select attr1, attr2, attr3, ...",
"from table1, table2, table3, ...",
"where ..."
].join(' ')
这个建议的优点在于，自动缩进器可以适当地缩进文档和长字符串的每个部分。但这是以效率为代价的。
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
你也可以使用双引号
x = """
this is
a multiline
string
"""
2.3.3 :012 > x
=> "\nthis is\na multiline\nstring\n"
如果需要删除换行符“\n”，请在每行末尾使用反斜杠“\”
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
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
