Declare @Age int Declare @Name varchar(20) Declare Cur Cursor For Select Age,Name From T_User Open Cur Fetch next From Cur Into @Age,@Name While @@fetch_status=0 Begin Update T_User Set [Name]=@Name,Age=@Age Fetch Next From Cur Into @Age,@Name End Close Cur Deallocate Cur
在实际应用时，经常需要找到这个模板，然后再根据实际的表结果，重写一遍。经常遇到以下二个问题 1 上面的例子脚本不知道放在哪里了，或是有很多例子脚本，不方便很快找出来 2 重写游标的例子，经常重复，又没有技术难度可言。比如读取工作单生产计划，读取用户。 经过思考，于是写个游标生成工具，把上面的模板代码，应用到代码生成器中。 注意上图中的Script Cursor，这是用来生成游标模板的。选择一个数据库，树左边选择表名，勾选字段值，点击执行 DECLARE @UserID NVARCHAR(10) DECLARE @UserName NVARCHAR(50) DECLARE Cur CURSOR FOR SELECT [UserID],[UserName] FROM [USER] OPEN Cur FETCH next FROM Cur INTO @UserID,@UserName WHILE @@fetch_status=0 BEGIN FETCH next FROM Cur INTO @UserID,@UserName END CLOSE Cur DEALLOCATE Cur
源代码不到50行，全文如下 List<ColumnInfo> fieldlist = this.GetFieldlist(); StringBuilder builder=new StringBuilder(); string typeName = string.Empty; foreach (ColumnInfo columnInfo in fieldlist) { switch (columnInfo.TypeName) { case "datetime": case "int": case "image": case "bit": typeName = columnInfo.TypeName; break; case "nvarchar": case "nchar": case "varchar": case "char": typeName =string.Format("{0}({1})", columnInfo.TypeName,columnInfo.Length); break; } builder.AppendLine(string.Format("Declare @{0} {1}", columnInfo.ColumnName, typeName)); } var columns = string.Join(",", (from column in fieldlist select "["+column.ColumnName+"]").ToArray()); string fetchNex= string.Join(",", (from column in fieldlist select "@"+column.ColumnName).ToArray()); string update= string.Join(",", (from column in fieldlist select "@"+column.ColumnName+"=["+ column.ColumnName+"]").ToArray()); builder.AppendLine(string.Format("Declare Cur Cursor For Select {0} From [{1}] ", columns, this.tablename)); builder.AppendLine("Open Cur"); builder.AppendLine(string.Format("Fetch next From Cur Into {0} ", fetchNex)); builder.AppendLine("While @@fetch_status=0 "); builder.AppendLine("Begin"); //builder.AppendLine(string.Format(" Update [{0}] Set {1} ",this.tablename,update)); builder.AppendLine(string.Format(" Fetch next From Cur Into {0} ", fetchNex)); builder.AppendLine("End "); builder.AppendLine("Close Cur "); builder.AppendLine("Deallocate Cur");
有以下几点需要注意 1 生成的脚本中，字段名称，表名称，均要加上方括号，以避免名称重突。 2 最后生成的SQL源代码，还需要应用下面的方法，将SQL关键字大写。 将SQL查询语句的关键字大写的方法来自CSDN下载区，全文如下 private static Regex RegexSQLCapitalize = new Regex("\badd\b|\baggregate\b|\baction\b|\balter\b|\bas\b|\basc\b|\basymmetric\b|\bauthorization\b|\bbegin\b|\bbinary\b|\bbit\b|\bby\b|\bcascade\b|\bcase\b|\bcatalog\b|\bcharacter\b|\bchar\b|\bcheck\b|\bcheckpoint\b|\bclose\b|\bclustered\b|\bconstraint\b|\bcollate\b|\bcolumn\b|\bcommit\b|\bcontains\b|\bcontinue\b|\bcreate\b|\bcross\b|\bcursor\b|\bdatabase\b|\bdeallocate\b|\bdesc\b|\bdecimal\b|\bdeclare\b|\bdefault\b|\bdelete\b|\bdesc\b|\bdistinct\b|\bdouble\b|\bdrop\b|\belse\b|\bend\b|\bescape\b|\bexcept\b|\bexec\b|\bexecute\b|\bexternal\b|\bfetch\b|\bfloat\b|\bforeign\b|\bfor\b|\bfrom\b|\bfunction\b|\bget\b|\bgroup\b|\bgoto\b|\bgrant\b|\bhaving\b|\bidentity\b|\binto\b|\bindex\b|\binsert\b|\binstead\b|\bint\b|\bkey\b|\bname\b|\bof\b|\bon\b|\bopen\b|\boption\b|\border\b|\boutput\b|\bprimary\b|\breturn\b|\brollback\b|\bschema\b|\bselect\b|\bsize\b|\bsymmetric\b|\bset\b|\bserver\b|(\btable\b)|\bthen\b|\btop\b|\btime\b|\btimestamp\b|\bto\b|\btrigger\b|\bprocedure\b|\btype\b|\bunion\b|\bunique\b|\bupdate\b|\buse\b|\bvalues\b|\bvalue\b|\bvarchar\b|\bview\b|\bwhen\b|\bwhile\b|\bwhere\b|\bwith\b|\bnvarchar\b|\bnchar\b|\bdatetime\b|\bfloat\b|\bdate\b|\bdatediff\b|\bdateadd\b|\bdatename\b|\bdatepart\b|getdate|\breferences\b|\babs\b|\bavg\b|\bcast\b|\bconvert\b|\bcount\b|\bday\b|\bisnull\b|\blen\b|\bmax\b|\bmin\b|\bmonth\b|\byear\b|\breplace\b|\bsubstring\b|\bsum\b|\bupper\b|\buser\b|\ball\b|\bany\b|\band\b|\bbetween\b|\bexists\b|\bin\b|\binner\b|\bis\b|\bjoin\b|\bleft\b|\blike\b|\bnot\b|\bnull\b|\bor\b|\bright\b|\btry\b|\bcatch\b", RegexOptions.IgnoreCase); public static string CapitalizeSQLClause(string source) { //先按行划分 Regex rowReg = new Regex("rn"); string[] strRows = rowReg.Split(source); StringBuilder strBuilder = new StringBuilder(); int rowsCount = strRows.Length; for (int i = 0; i < rowsCount; i++) { //去掉一行中的一个或多个空白 //strRows[i] = Regex.Replace(strRows[i], @"s+", " "); //按空格划分 string[] strWords = strRows[i].Split(new char[' ']); int wordsCount = strWords.Length; for (int j = 0; j < wordsCount; j++) { strBuilder.Append(" "); if (RegexSQLCapitalize.IsMatch(strWords[j])) { MatchCollection mc = RegexSQLCapitalize.Matches(strWords[j]); int mcmcCount = mc.Count; for (int k = 0; k < mcCount; k++) { strWords[j] = strWords[j].Replace(mc[k].Value, mc[k].Value.ToUpper()); } strBuilder.Append(strWords[j]); } else { strBuilder.Append(strWords[j]); } strBuilder.Append(" "); } strBuilder.Append("rn"); } return strBuilder.ToString().Replace("rnrn", "rn"); }
正则表达式替换字符串中的关键字，这个方法没有任何依赖，可拷贝到您的项目或类库中，为SQL 脚本增加关键字大写功能。 3 SQL 脚本格式化功能 假如能把生成的SQL脚本格式化一下，生成美观的SQL脚本，增加可读性。SQL Pretty Printer可以做到，但是没有找到API可以调用这个功能。 4 多表关联的游标模板没有做到。应该尝试从多个关联表中生成游标。不过表与表之间的关系难以自动生成，比如像下面的母子表游标询语句 Declare Cur Cursor For Select r.Description,r.WorkCenter FROM JobOrder j, JobOrderRouting r WHERE j.JobNo=r.JobNo Open Cur
游标要从2个关联的表中读取数据，假如2个表之间有外键关联，可以生成2个表的外键关联字段的关系，也就是上面的SQL游标可以自动生成，但是有的2个表之间没有外键关联的，还是要手工指定，相当于是个半成品的游标生成器，于是只好把这个功能点拿掉，只做最简单的一种情况，生成一个表的若干个字段的游标查询，没有设计多表查询的游标。 原文链接：http://www.cnblogs.com/JamesLi2015/archive/2013/05/20/3088024.html
SQL Server游标生成工具
出处：ITJS
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