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问题 Problem I am trying to write a Single Page Application (SPA) where initially the app shows module "A". When the user clicks an element in "A", module "B" is displayed and is passed an ID from A. (For example A displays a list of Employee IDs, clicking on one employee means B will display details of that employee) Initially my URL is : http://localhost:8000/ Clicking on an item in A with an id of 123, the URL changes to following which is correct: http://localhost:8000/A/123 However, I get the

问题 Problem I am trying to write a Single Page Application (SPA) where initially the app shows module "A". When the user clicks an element in "A", module "B" is displayed and is passed an ID from A. (For example A displays a list of Employee IDs, clicking on one employee means B will display details of that employee) Initially my URL is : http://localhost:8000/ Clicking on an item in A with an id of 123, the URL changes to following which is correct: http://localhost:8000/A/123 However, I get the

问题 i am trying to import an excel file into a datatable in using Jet.Oledb . Here is my code: string sourceConstr = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source='" + HttpContext.Current.Server.MapPath("~/" + fileName) + "';Extended Properties='Excel 8.0;HDR=No;IMEX=1'"; OleDbConnection con = new OleDbConnection(sourceConstr); OleDbCommand oleDbCmd = new OleDbCommand(); con.Open(); oleDbCmd.Connection = con; DataTable dt = con.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null); string

问题 Here is a code snippet: Private Sub frmSearch_UnMarkAll() Const sqlD As String = "DELETE * FROM PickList WHERE TableName = ""CARS"" AND KeyNo IN (" & _ "SELECT RecNo FROM Cars " If frmSearch.WhereSql <> vbNullString Then CurrentDb.Execute sqlD & frmSearch.WhereSql & ")" End If Stop End Sub This function is called by clicking a command button on the frmSearch form. The button raises an event that is handled by the above code. WhereSql is the where clause from the listbox displayed on the find

问题 Here is a code snippet: Private Sub frmSearch_UnMarkAll() Const sqlD As String = "DELETE * FROM PickList WHERE TableName = ""CARS"" AND KeyNo IN (" & _ "SELECT RecNo FROM Cars " If frmSearch.WhereSql <> vbNullString Then CurrentDb.Execute sqlD & frmSearch.WhereSql & ")" End If Stop End Sub This function is called by clicking a command button on the frmSearch form. The button raises an event that is handled by the above code. WhereSql is the where clause from the listbox displayed on the find

问题 I can read XLS file with this code : string path =@"c:\r\1.xlsx"; OleDbConnection MyConnection = new OleDbConnection(@"provider=Microsoft.ACE.OLEDB.12.0;Data Source='" + path + @"';HDR=Yes;Jet OLEDB:Engine Type=37"); OleDbDataAdapter MyCommand = new OleDbDataAdapter("select * from [Sheet1$]", MyConnection); DataSet DtSet = new DataSet(); MyCommand.Fill(DtSet); ... ... However - when I enhance the query to include some SQL Server commands like select *,case when 1=1 then 'a' else 'b' end as rr

问题 If I have an MS Access database with linked tables from two different database servers (say one table from an SQL Server db and one from an Oracle db) and I write a query which JOINs those two tables, how will Access (or the Jet engine, I guess?) handle this query? Will it issue some SELECTs on each table first to get the fields I'm JOINing on, figurre out which rows match, then issue more SELECTs for those rows? 回答1: The key thing to understand is this: Are you asking a question that Access

问题 I have used some code to import a text file into Excel using ADO as shown below: Sub ImportTextFile() 'Imports text file into Excel workbook using ADO. 'If the number of records exceeds 65536 then it splits it over more than one sheet. Dim strFilePath As String, strFilename As String, strFullPath As String Dim lngCounter As Long Dim oConn As Object, oRS As Object, oFSObj As Object 'Get a text file name strFullPath = Application.GetOpenFilename("Text Files (*.txt),*.txt", , "Please select text

问题 I'm writing some code in VBA behind Excel to pull some summary numbers out of potentially huge text files (10M+ rows) out on a network drive. In the past, these numbers have been pulled using greps in linux, but I was hoping to implement something that could be done with a click of a button in Excel for ease of use. My solution works, but it's like 25 times slower than a linux grep - takes 4 minutes to query 10M records, while the grep can do it in 10 seconds. Should I not be using ADO for

问题 Does the following article apply to all uses of JET (including from within client apps via DAO or OLEDB): http://support.microsoft.com/kb/275058 Does this mean JET 4.0 or above is mandatory for anything involving an Access MDB? 回答1: Unfortunately, the KB article is worded poorly. The SQL 92 syntax to which they refer is when you add a non-column comparison filter in the ON clause of an OUTER join (which also means it will not be viewable in the QBE). Thus, a standard outer join (LEFT or RIGHT