I have a data logging application that stores data in a table in a MySQL database. Data with a TimeStamp is logged into the table anytime the data from the sensor changes. This means that there maybe 2 seconds between data points or there maybe 20 seconds between points depending on how the data is changing.
When I need the data I have 2 dates and use this command to fill a table..SELECT FROM myTable WHERE timeStamp > date1 AND timeStamp < date2 This gets all the data that has a TimeStamp between the given dates, but in most case the first date in the returned table will be after date1, so I need to get the data from one row before the date returned in the table to know what the data was at date1.How can I get the data row that immediately precedes the returned data set?
I have a problem inserting data into a table on a MySQL database using a VB.NET application. I have a simple form where when I set some data to the textboxes and I press a GO button, the code should execute a function called InsertCar() that takes all these values and insert them into the database and then return true if the transaction is done successfully or false otherwise. My problem is that nothing is being inserted into the table.
Imports MySql.Data.MySqlClient Imports System.Data.Sql Imports System Imports System.Data
I'm developing a new programme that uses multiple table to store Orders placed via my website, on the form that i have created i have a Combobox that displays the Point of sale name. what i need it to do is when the record is updated in need the Point_of_sale_ID value that matches the name from the Point_Of_Sale table to be put into the Point_of_Sale_ID field on the Sales_Order tableI have added the Foreign Keys for the fields, but i cannot find any help in regards to this, i mainly wor with PHP but have taken on the new challenge of VB & ADO.Net, i have rear several book on the subject and have produced several single table programs but am now stuck!! [code]
Im trying to fumble my way through selecting data from a mysql table and populating it to a combo box. I feel Im almost there, could someone look over my code and see whats going wrong?
Private Sub ComboBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ComboBox1.SelectedIndexChanged Dim con As New MySqlConnection
I wish to delete the contains of multiple tables, and I also wish to append the contain of table1 to table2 (both table1 and table 2 have the same exact fields and type).For the Delete, I have tried the following code and I have undefined errors for SqlCommand and CommandType.This is my code for deleting the contains of a table:
Dim queryString As String = "DELETE FROM Buffer Table 1"[code].....
I am create a mysql table with TIME Data type fields. Like FROMTIME and TOTIME. And some insert data to that table. And that data is view through DataGridView. I can show all data in DATAGRIDVIEW. But, Have a error data, when current row click time ( Error data is : DataGridViewTextCell {ColumnIndex=0,RowIndex=0}.
I have a Form1 that is the main application form, that display certain data from a database. Then I have Form2 that add/delete data from a specific table in the database.My problem is, When I add data to the database, and save it, it work fine, But, it does not reflect on the main form, after I close Form2. Only when I exit the application, and open it again, it shows. Is there a setting or something I need to do to update/refresh the info added so I do not need to restart the application?
I am using vb2008 express to work an Access 2003 database. I want to use code to delete the table after I have used it and before I close the program. Is there any code to accomplishg this?
How can use vb.net forms to add or delete quantity in a field og ms sql data table.. EG: like in stock, we hv to add purchased stock and deduct selled stock.
if it affects the run time of a program if I were to have multiple data tables as opposed to one data table with all my data in it? I am trying to minimize datagrids and just use code to access table data, in hopes that it will speed up my program. But I am ignorant if multiple tables vs 1 main table will make a difference because there will still be the same amount of overall data present in my program one way or the other....?
I am using vb.net with phpMyAdmin MySql database. While running the piece of code below, the program hangs in the for loop before the variables are assigned values from the data table(dt)...
'Check for appraisal period----------------------------------------------------------------------- Dim sqlCheckDate As String = "SELECT * FROM tblappraisalsetting where appSetID=(select max(appSetID) from tblappraisalsetting);"
my system is kinda doctor gives prescription and medicine, and store related information into database. The case is when a doctor give few medicines to patient, those information have to store in a "RecordID" with few"ItemID" [Code]. anyone knows how to solve my problem, or any similar sample project can give me to refer? [Code].
I populate a datatable using a dataadapter. the select query pulls data from a view in which I combine multiple tables. Now I need to run different update statement etc to update each table. foe example I will update balance field in the accounts table using one query and another to update days present etc.
how should i do this? must i loop through each row in my datagridview?
I'm trying to delete a number of records in a table from the last and forward. My idea is to use sql like this: delete top " & variable & " * from table where ID = something It gives me a general sytax error. Is it at all possible? Fuga. Edit: I also have the order by statement there. I just forgot to put it in the question.
I am combining data from multiple tables into one table for a presentation software. I am doing a select statement and running a loop. Inside that loop I have multiple selects and I build a datatable an enter the data into the main table. There is a ton of records and it takes forever.
'Requisition Demands InsertStr = "SELECT COUNT(*) FROM Requisition WHERE (DMD_DT = " & dateVal & ") AND (QTY_REQ > QTY_PEND_CANC + QTY_CANC + QTY_REJT) " & searchvalString
*WeightCheck is a dataset connected to a mdf SQL server file..Datagrid on form is bound to the dataset..This code executes because datagrid on form updates with the deletions..[code]