I have to update table on SQL Server but first i have to check for existing data in table so if data is there update it, if not make a new insert:
cmd_sql.CommandText = " SELECT BrDok as id_dok " +
" FROM ordersstavke " +
" WHERE SifParFil = '" + rw_mat["sifskl_kor"] + "'" +
" AND DokumentTip = '" + rw_mat["vrst_dok"] + "'";
MySqlDataAdapter sql_adapter = new MySqlDataAdapter(cmd_sql);
DataSet dt_dok = new DataSet("DOK_MAT_EXCHANGE");
sql_adapter.Fill(dt_dok);
if (dt_dok.Tables["DOK_MAT_EXCHANGE"].Rows.Count == 0)
{
myQuery = " INSERT INTO ordersstavke (BrDok, DocumentTip, SifParFil) " +
" VALUES ('" + rw_mat["brdok"] + "', '" +
rw_mat["vrst_dok"] + "', '" +
rw_mat["sifskl_kor"] + "')";
}
else
{
UPDATE DATA
}
But I have an error in the code, the error is here if (dt_dok.Tables["DOK_MAT_EXCHANGE"].Rows.Count == 0)
Object reference not set to an instance of an object.
The problem is in this if statement...
DOK_MAT_EXCHANGE is the name of the DataSet, not of the first table.
You should test with
if (dt_dok.Tables[0].Rows.Count == 0)
Also, I think is better to use a syntax like this to discover how many records are presents
cmd_sql.CommandText = "SELECT COUNT(BrDok) as id_dok " +
" FROM ordersstavke " +
" WHERE SifParFil = ?p1 " +
" AND DokumentTip = ?p2";
cmd_sql.Parameters.AddWithValue("?p1", rw_mat["sifskl_kor"] );
cmd_sql.Parameters.AddWithValue("?p2", rw_mat["vrst_dok"] );
int rowCount = (Int32)cmd_sql.ExecuteScalar();
change
DataSet dt_dok = new DataSet("DOK_MAT_EXCHANGE");
to
DataSet dt_dok = new DataSet("ordersstavke ");
and
if (dt_dok.Tables["DOK_MAT_EXCHANGE"].Rows.Count == 0)
to
if (dt_dok.Tables["ordersstavke "].Rows.Count == 0)
Accessing the first table via the dataset name is incorrect, that's for setting the XML.
Instead use
dt_dok.Tables[0].Rows.Count;
That being said, you're better off writing this as a single SQL statement instead of a separate select && insert. This way you're not going to the DB multiple times.
var sql = #"if exists(select * from ordersstavke where SifParFil = ? and DokumentTip = ?)
then
-- do insert statement
else
-- do update
end if";
This might also be better done with a stored proc, so you don't have as much SQL code in C#. It's easier to manage multiple operations that way.
And for crying out loud, use SqlParameters, not string concatenation! That's just asking for trouble!
Ok, thanks guys, I wrote it like this
if (ds_dok.Tables[0].Rows.Count <= 0)
{
myQuery = " INSERT INTO ordersstavke (BrDok, " +
" SifParFil) " +
" VALUES ('" + rw_mat["brdok"] + "', '" +
rw_mat["sifskl_kor"] + "')";
}
else if (ds_dok.Tables[0].Rows.Count >= 1)
{
myQuery = "UPDATE ordersstavke " +
"SET BrDok = '" + rw_mat["brdok"] + "', " +
"SifParFil = '" + rw_mat["sifskl_kor"] + "', " +
"WHERE BrDok = " + ds_dok.Tables["ordersstavke"].Rows[0]["BrDok"].ToString() + "'";
}
But there is a small problem in the section update: s_dok.Tables["ordersstavke"].Rows[0]["BrDok"].ToString(), here it give me that loving error : Object reference not set to an instance of an object.
Maybe the update on MySQL goes on different way, I'm referencing on example on sql server and there update goes differently
Related
I am currently reading and parsing 10 different file(.txt, .csv), each file has a different number of columns.
Here is a sample from one file:
SqlCommand cmd = new SqlCommand("insert into " + table_name + " VALUES('"+data_from_file[0]+"', '" + data_from_file[1] + "', '" + data_from_file[2] + "', '" + data_from_file[3] + "', '" + data_from_file[4] + "','" + data_from_file[5] + "', '" + data_from_file[6] + "', '" + data_from_file[7] + "', '" + data_from_file[8] + "', '" + data_from_file[9] + "');", connection);
cmd.ExecuteNonQuery();
This file has a total of 10 columns that gets inserted into its own table. If I do it like this for the 10 files, I would have 10 different if/else if statements. And to me that sounds like bad way of doing this. Is there a way to iterate through the array and insert each element? I have been looking for ways to do it, but cannot find a proper solution for my problem. Thanks for the help.
The most classical way would be to iterate and append to a string and then execute:
string command = "insert into " + table_name + " VALUES(";
foreach(string data in data_from_file)
{
command += "'" + data + "',";
}
command = command.TrimEnd(','); // remove the last extra ','
command += ");";
SqlCommand cmd = new SqlCommand(command);
cmd.ExecuteNonQuery();
However, I recommend that you have a look at SqlBulkCopy for Large Insert Queries.
First you iterate over your collection, and then you insert every entry from the collection into the database.
foreach (var oneColumn in data)
{
SqlCommand cmd = new SqlCommand("INSERT INTO " + table_name + " VALUES(" + oneColumn + ")");
cmd.ExecuteNonQuery();
}
This is my code:
OleDbConnection con = new OleDbConnection("provider=microsoft.jet.oledb.4.0;data source=" + Application.StartupPath + "/shoping mall.mdb");
con.Open();
OleDbCommand cmd = new OleDbCommand("update RecordofItems set RecordofItems.Bill_no = " + textBox1.Text + ", RecordofItems.Received_from = '" + textBox62.Text + "', RecordofItems.Item_Code = " + textBox2.Text + ", RecordofItems.Quantity = " + textBox32.Text + ", RecordofItems.Sale_Rate = " + textBox47.Text + " where Item_Name = '" + textBox17.Text + "'", con);
int x = 0;
x = cmd.ExecuteNonQuery();
if (x > 0)
{
MessageBox.Show("record deleted" + x);
}
else
{
MessageBox.Show("no record exixt");
}
con.Close();
I want to update selected columns in my "RecordofItems" table that has 10 columns but I want to update only 6 selected columns, when I run the query it shows error "no value for one or more required paremeter" What to do ? please help me as soon as you can.
the error No value given for one or more required parameters usually comes when you have misplaced single quote.
try these two.
try assigning your numerical db columns a numerical value viz update your query with these:
RecordofItems.Bill_no = " + Convert.ToInt32(textBox1.Text) + ",
RecordofItems.Item_Code = " + Convert.ToInt32(textBox2.Text) + ",
RecordofItems.Quantity = " + Convert.ToInt32(textBox32.Text) + ",
RecordofItems.Sale_Rate = " + Convert.ToInt32(textBox47.Text) +
or use whatever suitable numerical converter applies to your columns.
one of your text fields might have a single quote in it, so try replacing/updating your text fields like this:
RecordofItems.Received_from = '" + textBox62.Text.Replace("'","''") + "',
so basically, replace single quote with two single quotes.
see if these solve your issue.
Also, do note, never create your sql query by concatenating textboxes(strings). use command parameters. they will save you from sql injection.
I have data set that is being filled from sql query, like this
cmd_sql.CommandText = " SELECT BrDok " +
" FROM ordersstavke " +
" WHERE SifParFil = '" + rw_mat["sifskl_kor"] + "'";
MySqlDataAdapter sql_adapter = new MySqlDataAdapter(cmd_sql);
DataSet ds_dok = new DataSet("ordersstavke");
sql_adapter.Fill(ds_dok);
Now I want to extract value from data set for sql update, like this one
myQuery = "UPDATE ordersstavke " +
"SET BrDok = '" + rw_mat["brdok"] + "', " +
"SifParFil = '" + rw_mat["sifskl_kor"] + "', " +
"WHERE BrDok = " + ds_dok.Tables["ordersstavke"].Rows[0]["BrDok"] + "'";
I tried this ds_dok.Tables["ordersstavke"].Rows[0]["BrDok"] but I got an error,
I was thinking to do something like this
string BrDok;
BrDok = ds_dok.["BrDok"].ToString();
But nothing, how to extract that BrDok or just put it into procedure?
Thanks infront!
Make it
DataSet ds_dok = new DataSet("ordersstavke");
sql_adapter.Fill(ds_dok,"BrDok");
Then use
ds_dok.Tables["BrDok"].Rows[0]["BrDok"].ToString()
Try this
ds_dok.Tables[0].Rows[0]["BrDok"]
If you provide a string argument for the dataset class, then it will be the dataset name and not the datatable name. And there is no table in the database with name you provided for a dataset, so give it while filling the dataset. Write some thing like below.
DataSet ds_dok = new DataSet();
sql_adapter.Fill(ds_dok,"ordersstavke");
and you can write all the remaining code as it is in your code part.
And your second update query has some syntax error, see it like below
myQuery = "UPDATE ordersstavke " + "SET BrDok = '" + rw_mat["brdok"] + "', "
+ "SifParFil = '" + rw_mat["sifskl_kor"] + "', " + "WHERE BrDok
= '" + ds_dok.Tables["ordersstavke"].Rows[0]["BrDok"] + "'";
You forgot to put an starting inverted comma at the where clause.
Just a small hint to the sql-command. You should use sql-parameters to prefent sql-injection.
I have a question, how to parse datetime value from Oracle to MySQL database.
I wrote this to extract a datetime from Oracle:
SELECT TO_CHAR(p1.creation_date,'DD.MM.RRRR HH24:mi:ss') AS dat_pot
FROM TABLE
then I put the result into data set, then I extract the value of date from dataset like this:
string lDat_otp = null;
if (rw_mat["dat_otp"].ToString().Length <= 0)
{
lDat_otp = "0";
}
else
{
lDat_otp = "convert(datetime,'" + rw_mat["dat_otp"] + "',4)";
}
Then I use lDat_otp in INSERT statement with some other values like this:
myQuery = " INSERT INTO ordersstavke (BrDok, " +
" SifParFil, SifParIsp, DatPriOtpr, SifPodKla, Masa, Paketa) " +
" VALUES ('" + rw_mat["brdok"] + "', '" +
rw_mat["sifskl_kor"] + "','" +
rw_mat["partner"] + "'," +
lDat_otp + ",'" +
rw_det["ibrmat"] + "', '" +
rw_det["izlaz_tez"] + "', '" +
rw_det["izlaz_kol"] + "')";
But there is an error on execute and it goes:
You have an error in your SQL syntax; check the manual that
corresponds to your MySQL server version for the right syntax to use
near '26.01.2012 13:48:41',4)','100654', '0', '10')' at line 1
So help!!!
You can parse the datetime field into a DateTime struct and then create an insert into query with parameters and pass the date as parameter :
DateTime time = //Some value ...
String myQuery = " INSERT INTO ordersstavke (BrDok, " +
" SifParFil, SifParIsp, DatPriOtpr, SifPodKla, Masa, Paketa) " +
" VALUES ('" + rw_mat["brdok"] + "', '" +
rw_mat["sifskl_kor"] + "','" +
rw_mat["partner"] + "'," +
"?date ,'" +
rw_det["ibrmat"] + "', '" +
rw_det["izlaz_tez"] + "', '" +
rw_det["izlaz_kol"] + "')";
MysqlCommand command = new MysqlCommand(query, connection);
command.Parameters.AddWithValue("?date", time);
Doing this you should not have problems with date formatting.
I strongly suggest to use parameters instead of string concatenation even for the others parameters of the query ...
I've tried this:
select * from ourschema.mytable
where contains(mysearchablefield, #searchTerms) = 1;
Where #searchTerms was set to "search terms"
Unfortunately, it only produced an error:
ERROR [42610] [IBM][DB2/NT] SQL0418N A statement contains a use of a parameter marker that is not valid. SQLSTATE=42610
Is there a way to use parameterized queries for text search with DB2? If not, is there a document which describes the syntax in detail for manual (ugh) escaping of the search terms (quotes, etc)?
Instead of #field you need to use "?". Everything is basically the same.
Okay, here is a live code sample.
sqlStmt = "SELECT COMPLAINT_NUMBER, VIOLATION_NUMBER, COMMON_ADDRESS_KEY, " +
"DEPT_CODE, DEPT_CODE_DESC, DIVISION_CODE, DIVISION_CODE_DESC, " +
"EMPLOYEE_NAME, COMPLAINT_CODE, COMPLAINT_CODE_DESC, COMPLAINT_DATE, " +
"COMMON_ADDRESS_OWNER, RESOLUTION_CODE, 1 AS SORTORDER " +
"FROM QMFILES/NVMASTP " +
"WHERE VCLOSEDATE = 0 AND " +
"DEPT_CODE LIKE #DEPT_CODE1 AND " +
"DIVISION_CODE LIKE #DIVISION_CODE1 AND " +
"COMPLAINT_DATE BETWEEN #FROM_COMPLAINT_DATE1 AND #TO_COMPLAINT_DATE1 " +
statusQry +
"UNION " +
"SELECT COMPLAINT_NUMBER, VIOLATION_NUMBER, COMMON_ADDRESS_KEY, " +
"DEPT_CODE, DEPT_CODE_DESC, DIVISION_CODE, DIVISION_CODE_DESC, " +
"EMPLOYEE_NAME, COMPLAINT_CODE, COMPLAINT_CODE_DESC, COMPLAINT_DATE, " +
"COMMON_ADDRESS_OWNER, RESOLUTION_CODE, 2 AS SORTORDER " +
"FROM QMFILES/NVMASTP " +
"WHERE VCLOSEDATE <> 0 AND " +
"DEPT_CODE LIKE #DEPT_CODE2 AND " +
"DIVISION_CODE LIKE #DIVISION_CODE2 AND " +
"COMPLAINT_DATE BETWEEN #FROM_COMPLAINT_DATE2 AND #TO_COMPLAINT_DATE2 " +
statusQry +
"ORDER BY DEPT_CODE, DIVISION_CODE, COMPLAINT_CODE, SORTORDER";
iDB2Command cmd = new iDB2Command(sqlStmt, conn);
conn.Open();
cmd.DeriveParameters();
conn.Close();
cmd.Parameters["#DEPT_CODE1"].Value = dept;
cmd.Parameters["#DIVISION_CODE1"].Value = serviceArea;
cmd.Parameters["#DEPT_CODE2"].Value = dept;
cmd.Parameters["#DIVISION_CODE2"].Value = serviceArea;
cmd.Parameters["#FROM_COMPLAINT_DATE1"].Value = Convert.ToDecimal(fromDateString);
cmd.Parameters["#TO_COMPLAINT_DATE1"].Value = Convert.ToDecimal(toDateString);
cmd.Parameters["#FROM_COMPLAINT_DATE2"].Value = Convert.ToDecimal(fromDateString);
cmd.Parameters["#TO_COMPLAINT_DATE2"].Value = Convert.ToDecimal(toDateString);
I hope this helps you out more.