查询中涉及到sum()函数和substr函数组合
sum( SUBSTR( xxx,3,1 ) = 5 OR SUBSTR( xxx,3,1 ) = 6 ) as sum,
运行后结果不正确,打印sql发现substr内参数被替换为:
sum( SUBSTR( xxx,1 ) = 5 OR SUBSTR( xxx,1 ) = 6 ) as sum,
解决办法,将substr中,分割使用表述语法代替:
sum( SUBSTR( xxx FROM 3 FOR 1 ) = 5 OR SUBSTR( xxx FROM 3 FOR 1 ) = 6 ) as sum,
再次运行,结果达到预期