mysql内联子视图查询注意点

在进行内联子视图查询的时候，报Every derived table must have its own alias错误。

其中查询语句是SELECT count(*) FROM ( SELECT DISTINCT library FROM mutation_information WHERE chr='chr13' AND pos='32906729' AND ref='A' AND alt='C' AND current_result='良性')

我们只需要改为SELECT count(*) FROM ( SELECT DISTINCT library FROM mutation_information WHERE chr='chr13' AND pos='32906729' AND ref='A' AND alt='C' AND current_result='良性') AS total，给个别名既可。原因是因为mysql中，新返回的视图是个派生表，所有派生表都要有个别称。