ORA-01859: a non-alphabetic character was found where an alphabetic was expected
文档解释ORA-01859:anon-alphabeticcharacterwasfoundwhereanalphabeticwasexpectedCause:Theinputdatatobeconvertedusingadateformatmodelwasincorrect.Theinputdatadidnotcon...
ORA-01858: a non-numeric character was found where a numeric was expected
文档解释ORA-01858:anon-numericcharacterwasfoundwhereanumericwasexpectedCause:Theinputdatatobeconvertedusingadateformatmodelwasincorrect.Theinputdatadidnotcontainanu...
MySQL Error number: MY-011683; Symbol: ER_GRP_RPL_SINGLE_PRIM_MODE_NOT_ALLOWED_WITH_UPDATE_EVERYWHERE; SQLSTATE: HY000
文档解释Errornumber:MY-011683;Symbol:ER_GRP_RPL_SINGLE_PRIM_MODE_NOT_ALLOWED_WITH_UPDATE_EVERYWHERE;SQLSTATE:HY000Message:Itisnotallowedtorunsingleprimarymodewith&#...
小心 List.Where 中 Lambda 表达式，性能问题
List<int> list = new List<int>();list.Add(1);list.Add(2);list.Add(3);// 写法一var obj = list.Where(m =>...
使用 Dictionary 代替 List.Where，提高速度
在C#中，有一List，有上万条数据项，每个数据项，又是一个类，List.Where去查找符合条件的类，然后计算，由于不断地调用List.Where，整个时间耗时约2分钟。不能忍受该时间。由于每调一次List.Where，就去循环一次，所以考虑使用Dictionary来代替，Where中判断条件，写作key，需要输出的...