How do you filter a SQL Null or Empty String? Anull valuein a database really means the lack of a value. It is a special “value” that you can’t compare to using the normal operators. You have to use a clause in SQL IS Null. On the other hand, an empty string is an actual...
在数据导入完成后进行数据同步,从库发生报错 1032 找不到记录,但是登录从库中可以查询到此条记录,这里就很奇怪; 最后通过解析relaylog,根据relaylog中的update记录,以每个字段为查询条件进行查询,发现是由于NULL值列导致的,主库这列的值是 NULL,从库在导入后导成了字符串"NULL",因此导致回放update操作时匹配不到...
Checking if String is NULL or EMPTY in SQL Cleaning strings of escape characters before passing to sql Column 'coloumname' does not belong to table categories . Column names in each table must be unique error... Combine first and last name columns in linq Command...
Checking if String is NULL or EMPTY in SQL Cleaning strings of escape characters before passing to sql Column 'coloumname' does not belong to table categories . Column names in each table must be unique error... Combine first and last name columns in linq Command...
目录COALESCE()函数ISNULL()COALESCE()函数COALESCE ( expression,value1,value2……,valuen) ;COALESCE()函数将会返回包括expression在内的所有参数中的第一个非空表达式。如果expression不为空值则返回expression;否则判断value1是否是空值,如果value1不为空值则返回value1;否则判断v ...
数据保存到Excel///////////////<returns></returns>staticasyncTaskSavePageExcel(TabInfo tableInfo, DataTable dt,stringsavePath,boolisNullTemplate, List<ColumnSetting> columnSettings =null){ Extension.Excel excel =newExtension.Excel(newExtension.ExcelOptions() { TempType = Extension.TempType.HEAD...
(5,'小黑',14,'北京',NULL); 2.3 查看数据 greatsql>select*fromt1; +---+---+---+---+---+ |id|name|age|addr|school| +---+---+---+---+---+ |1|小红|10|北京|一中| |2|小绿|11|北京|一中| |3|小黄|12|北京|NULL| |4|小蓝...
setRightExpression(new StringValue(tenantId)); if (Objects.isNull(original)) { return equalsTo; } return original instanceof OrExpression ? new AndExpression(equalsTo, new Parenthesis(original)) : new AndExpression(original, equalsTo); } private static Column getColumnWithTableAlias(FromItem table...
isFull()) { return "全连接"; } if (join.isCross()) { return "交叉连接"; } return null; } public static void getSelectMsg(Select select){ PlainSelect plain = (PlainSelect) select.getSelectBody(); List<Join> joins = plain.getJoins(); if (CollectionUtils.isNotEmpty(joins)) { for...
<isNotNull> 与<isNull>相反 <isEmpty> 如果属性为Collection或者String,其size是否<1, 如果非以上两种类型,则通过 String.valueOf(属性值) 获得其String类型的值后,判断其size是否<1 <isNotEmpty> 与<isEmpty>相反。 二、二元判定 二元判定有两个判定参数,一是属性名,而是判定值,如 ...