连接管线绑扎前，电线要留出点富余量，为的是（ ）.

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SQL Error: select id,body,options from ***_enewstiku where sourceid='25784' and id < 2166054 and id<>'2166054' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='25784' and id > 2166054 and id<>'2166054' order by id asc limit 5