I have a very simple database in Access 2007 that I'm connecting to using VB 2010. There are two tables, MenuItems and Orders, and Orders.orderDate is of type "Date".
I'm running the following code in one of my VB forms (the connection string and everything else is fine):
sql = "SELECT OrderDate, MenuItem FROM MenuItems, Orders WHERE Orders.itemID = MenuItem.ID AND Orders.orderDate BETWEEN '" + fromDate + "' AND '" + toDate + "'"
Dim cmd As New OleDb.OleDbCommand(sql, con)
Dim count As Integer = cmd.ExecuteNonQuery()
But I get an error that:
System.Data.OleDb.OleDbException (0x80040E10): value wan't given for one or more of the required parameters
Nothing seems to be missing. I've used the same code for another query, except the sql was different. But I think my sql is simple enough. Here's the sql that was generated in one instance (I've double checked, all table and column names are correct):
SELECT OrderDate, MenuItem From MenuItems, Orders WHERE Orders.itemID = MenuItem.ID AND Orders.orderDate BETWEEN '11/21/2012' AND '11/24/2012'
You should use parametrized queries for at least two reasons.
You don't have to worry about date (and other) literals and locale problems.
You don't have to worry about SQL injection attacks, where someone enters malicious code in a text box that turns a SQL statement into a harmful one.
Change your statement to
sql = "SELECT Orders.OrderDate, MenuItems.MenuItem " & _
"FROM MenuItems INNER JOIN Orders ON MenuItems.ID = Orders.itemID " & _
"WHERE Orders.orderDate BETWEEN ? AND ?"
Then execute the command like this
Dim fromDate, toDate As DateTime
fromDate = DateTime.Parse(fromDateTextBox.Text)
toDate = DateTime.Parse(toDateTextBox.Text)
Dim dataset As New DataSet()
Using conn As New OleDbConnection(connectionString)
Using adapter As New OleDbDataAdapter()
Dim cmd As New OleDbCommand(sql, conn)
cmd.Parameters.Add("?", fromDate)
cmd.Parameters.Add("?", toDate)
adapter.SelectCommand = cmd
adapter.Fill(dataset)
End Using
End Using
Well, the ExecuteNonQuery method is there for statements for changing data, ie. DELETE / UPDATE /INSERT, and the returned value are the number of rows affected by that statement.
Since you are using Select statement, you should be using oledbDataAdapter and Fil DataSet for use.
Dim conn As New OleDbConnection(con)
Dim adapter As New OleDbDataAdapter()
sql = "SELECT OrderDate, MenuItem FROM MenuItems, Orders WHERE Orders.itemID = MenuItem.ID AND Orders.orderDate BETWEEN '" + fromDate + "' AND '" + toDate + "'"
adapter.SelectCommand = new OleDbCommand(sql, con)
adapter.Fill(dataset)
Return dataset
The issue was a mis-spelled table. (MenuItem instead of MenuItems), but it didn't solve the question, I still got an error. It turned out to be a problem with matching formats between the database and the datepicker values being used as query parameters.
So I made sure I saved to the database in short Date Format:
sql = "INSERT INTO Orders(itemID, OrderDate) VALUES('" + ListBox1.SelectedValue.ToString() + "','" + FormatDateTime(OrderDate.Value, DateFormat.ShortDate) + "')"
Related
As the title says, I'm unable to filter an SQL sentence from access database with vb.net
Dim data1 As String = DateTimePicker1.Value.ToShortDateString
Dim data2 As String = DateTimePicker2.Value.ToShortDateString
Dim sql As String = "SELECT totais.* From totais Where totais.data Between #" + data1 + "# And #" + data2 + "#;"
It gives me random values. If i put 1-10(October)-2019 it gives me all the records in system, if i put 12-10(October)-2019 it only gives today's record (doesn't show yesterday and before records). I'm not finding the problem, can you please help?
Thanks
I would use Parameters instead of concatenating a string for the Sql statement. It makes the statement much easier to read and avoids syntax errors.
With OleDb the order that parameters appear in the sql statement must match the order they are added to the parameters collection because OleDb pays no attention to the name of the parameter.
Private Sub OPCode()
Dim sql As String = "SELECT * From totais Where data Between #StartDate And #EndDate;"
Using dt As New DataTable
Using cn As New OleDbConnection("Your connection string"),
cmd As New OleDbCommand(sql, cn)
cmd.Parameters.Add("#StartDate", OleDbType.Date).Value = DateTimePicker1.Value
cmd.Parameters.Add("#EndDate", OleDbType.Date).Value = DateTimePicker2.Value
cn.Open()
dt.Load(cmd.ExecuteReader)
End Using
DataGridView1.DataSource = dt
End Using
End Sub
You need to use single quotes and convert type in SQL like this:
SELECT totais.* FROM totais WHERE totais.data Between CDATE('" + data1 + "') And CDATE('" + data2 + "');"
You should use parameters as per Mary's answer BUT for completeness...
Ms/Access requires dates specified as #mm/dd/yy# so your SQL will only work properly where the local date time format is mm/dd/yy. i.e. mostly the US. Otherwise you will have to format your date string.
Im trying to select all records from a database table. Each record has a date in it i want to select all records where that date matches todays date
i created a variable called todaydate and used it within the query but i get No value provided for one or more required parameters error. What possible parameters would i use
Here is the code
Any help would be appreciated
Dim todaydate As Date = Date.Today()
If DbConnect() Then
Dim SQLCmd As New OleDbCommand
With SQLCmd
.Connection = cn
.CommandText = "Select * from Tbl_Rental Where DateOfHire = todaydate"
'parameters????
You're not using the variable. However, you should always use sql-parameters not concatenate strings(one reason: avoiding SQL-Injection). I'd also suggest to use the Using-statement for the connection and everything else that implements IDisposable:
Using cn As New OleDbConnection(connectionString)
cn.Open()
Using cmd As New OleDbCommand("Select * from Tbl_Rental Where DateOfHire = #DateOfHire", cn)
dim hireDateParameter As new OleDbParameter("#DateOfHire", OleDbType.Date)
hireDateParameter.Value = Date.Today
cmd.Parameters.Add(hireDateParameter)
' ... '
End Using
End Using
If it's always Date.Today you could do that also without a parameter because every database has date functions which return the current date. But since you haven't told us which DB you are using it's hard to show an example.
You need to actually use your variable, not include it as part of the string. Try this:
.CommandText = "Select * from Tbl_Rental Where DateOfHire = '" & todaydate.ToString("dd/MM/yy") & "'"
From a slightly different angle, would it suffice that the date was simply "greater than yesterday"?
.CommandText = "Select * from Tbl_Rental Where DateOfHire >= cast(getdate() as date)"
This strips the time off the date and anything at or later than midnight today is included.
My database program has a statement like:
variable = "SELECT * from Staff where StaffName = '" & cStaffName & "'"
This works fine until I have a member of staff with ' (apostrophe) in there name as it ends the start apostrophe.
SELECT * from Staff where StaffName = 'O'Conner'
Is there a way around this without replacing the apostrophe in her name?
You just need to use a parameterized query.
Using con = new SqlConnection(....)
Using cmd = new SqlCommand("SELECT * from Staff where StaffName = #name", con)
con.Open
cmd.Parameters.Add("#name", SqlDbType.NVarChar).Value = cStaffName
Using reader = cmd.ExecuteReader
.....
End Using
End Using
End Using
In this scenario you add a parameter to the SqlCommand parameters collection. The command text has no more a string concatenation but contains a parameter placeholder (#name). The parameter itself contains the value you want to pass to your query.
In this way there is no problem with quotes embedded in the value.
You also get the extra benefit to avoid any kind of Sql Injection problem with the user input
variable = "SELECT * from Staff where StaffName = '" & Replace(cStaffName, "'", "\'") & "'"
i have some problem with my SELECT Query to MS Access .mdb file.
i am using VB.Net and have to send query like..
"SELECT d_date, d_tons, d_qty, d_cost FROM [deal] WHERE DatePart(""m"", [d_date]) = '" _
+ DTP.Value.Month.ToString + "' AND ([d_client] = '" + cBoxClient.Text + "')"
But it doesn't work.. No Error in compiling but this Query cannot SELECT any data.
DTP is DateTimePicker, i select Month with DTP and filled some text into cBoxClient(ComboBox)
What's wrong with that Query? i have no idea because i always used MySQL and this is my first application development with MS Access..
Please HELP me.
Use parameterized query, that will save you from sql injection and complexity of converting specific data format (such as DateTime) to it's string representation that is valid according to database specific culture. For example :
Dim queryString = "SELECT d_date, d_tons, d_qty, d_cost FROM [deal] WHERE " & _
"DatePart(""m"", [d_date]) = ? AND ([d_client] = ?)"
OleDbCommand cmd = New OleDbCommand(queryString, connection)
cmd.Parameters.AddWithValue("#date", DTP.Value.Month)
cmd.Parameters.AddWithValue("#client", cBoxClient.Text)
I cannot seem to figure out how to get an output of a SQL query as a variable in VB. I need something like what's below so that I can use that variable in another SQL query. SQL doesn't allow the use of variables as column headers when running queries, so I thought I could use VB to insert the actual output of one SQL task as the dynamic variable in a loop of update queries. Let me (hopefully) explain.
I have the following query:
DECLARE #id int = (SELECT max(id) FROM [views]), #ViewType nvarchar(3);
WHILE #id IS NOT NULL
BEGIN
SELECT #ViewType = (SELECT [View] FROM [views] WHERE id = #id);
UPDATE a
SET a.[#ViewType] = '1'
FROM [summary] a
INNER JOIN [TeamImage] b
ON a.[Part_Number] = b.[PartNum]
WHERE b.[View] = #ViewType;
SELECT #id = max(id) FROM [views] WHERE id < #id;
END;
The SET a.[#ViewType] = '1' obviously will not work in SQL. But if I could have the (SELECT [View] FROM [views] WHERE id = #id) equal to a variable, then I could write the SQL query in VB and execute it and the variable would become part of the string and therefore execute correctly.
I'm newer to VB, but here's what I have so far:
Dim cn As SqlConnection = New SqlConnection("Data Source=Server1;" & _
"Initial Catalog=DB1;" & _
"Integrated Security=SSPI")
cn.Open()
Dim cmd As New sqlCommand("SELECT max(id) FROM orientation_view_experiment;", cn)
vID = cmd.ExecuteNonQuery()
Do While vID > 0
Dim cmd2 As New sqlCommand("SELECT [View] FROM [views] WHERE id ='" + vID + "'"
vViewType = cmd2.ExecuteNonQuery()
Dim cmd3 As New sqlCommand("UPDATE a
SET a.'" + vViewType + "' = '1' & _
FROM [summary] a & _
INNER JOIN [TeamImage] b & _
ON a.[Part_Number] = b.[PartNum] & _
WHERE b.[View] = '" + vViewType + "';"
cmd3.ExecuteNonQuery()
vID = vID - 1
Loop
cn.Close()
I hope some of that made sense, but I'm kind of lost at this point. I feel like I know what I need the SQL to do, but can't quite figure out how to make the computer/programs submit to my will and just do what I need it to do.
Thank you for any help/direction you can give.
Your code is wrong because you insist in using ExecuteNonQuery for SELECT statements. ExecuteNonQuery doesn't return the rows selected but just a count of the rows affected by an INSERT/DELETE/UPDATE query (I think that for SELECT it returns always zero)
What you need is ExecuteScalar to get the MAX value and the VIEW value because ExecuteScalar is the best choice when you expect to get just the first field of the first row from your SQL statement
Dim cmd As New sqlCommand("SELECT max(id) FROM orientation_view_experiment;", cn)
vID = Convert.ToInt32(cmd.ExecuteScalar())
Do While vID > 0
Dim cmd2 As New sqlCommand("SELECT [View] FROM [views] WHERE id =" + vID.ToString()
Dim result = cmd2.ExecuteScalar()
if Not string.IsNullOrEmpty(result)) Then
vViewType = result.ToString()
Dim cmd3 As New sqlCommand("UPDATE a SET a.[" + vViewType + "] = '1' " & _
"FROM [summary] a " & _
"INNER JOIN [TeamImage] b " & _
"ON a.[Part_Number] = b.[PartNum] " & _
"WHERE b.[View] = #vType"
cmd3.Parameters.AddWithValue("#vType", vViewType)
cmd3.ExecuteNonQuery()
End If
Loop
The last part of your code is not really clear to me, but you could use a couple of square brackets around the column name in table summary and a parameter for the View field in table TeamImage.
As a last advice, be sure that the column View in table TeamImage is not directly modifiable by your end user because a string concatenation like this could lead to a Sql Injection attacks
Do a little research into what the different methods of a command are. When you call ExecuteNonQuery, this return the number of records effected. I think you want ExecuteScalar as your cmd and cmd2 methods, so you can get a value from the database.
Have you tried replacing '" + vViewType + "' with [" + vViewType + "] ... in other words use square brackets to delimit the column name instead of single quotes which are for delimiting string literals?
Also, I would encourage stopping in the debugger, examining the command that you generated into cmd3 and try executing it directly. It might help you identify other similar problems such as the fact that vViewType is giving you a count of records instead of an actual value from the [View] column.