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hi,
I am using MySql .NET Connector 5.1.2.
Following is the code I am using to read a longblob field from a table..
string selCmd = "SELECT * FROM document";<br />
MySqlCommand allDocsCmd = new MySqlCommand(selCmd, con);<br />
MySqlDataReader reader = allDocsCmd.ExecuteReader();<br />
reader.Close();
The execution hangs at reader.Close();
When I selected everything else but the blob field from the table and it worked fine i.e.
"select id,data from document" hangs but
"select id from document" works ok.
('data' is a LONGBLOB field in document table)
I am searching a cause and fix but lemme know if anyone has ne idea why this is happening..
Thanx.
-- modified at 9:56 Wednesday 10th October, 2007
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hi!1
Actually i am a beginner with asp.net and databases .
i want to know that how can i access values from a table where some column name has null value say parentId ..
Mrinal
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what if one value is int type and the other is null type
Mrinal
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SqlDataReader r =//..some code..
int ParentId;
//short form
r.IsDBNull(r.GetOrdinal("ParentId"))?-1:Convert.ToInt32(r["ParentId"]);
OR
int ParentId = -1;
if (!r.IsDbNull(r.GetOrdinal("ParentId")))
{
ParentId = Convert.ToInt32(r["ParentId"]);
}
Intelligence is measured by common sense not by how many scholarly books you read.
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SELECT AField FROM ATable WHERE parentId is null
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Hi,
I have a simple doubt.The maximum number of parameters in a stored procedure is 2100.
Like what is the maximum number of stored procedure in a MSSQL database ????
Be very grateful for any advice.
Regards
All I ever wanted is what others have.... CrazySanker
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Vipin dev wrote: The maximum number of parameters in a stored procedure is 2100.
I find that would be hard to reach that number.
Have you looked around google for your question about the max. number of stored procs?
"Real programmers just throw a bunch of 1s and 0s at the computer to see what sticks" - Pete O'Hanlon
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Hi,
i am using sql server 2005 and i am writing one query to concatename 3 column values..
SELECT distinct(P.firstname + ' ' + P.middlename + ' ' + P.lastname) AS UserName ,P.Id as UserId,G.Id,G.Fkgroupid FROM c_Groupmember G,c_Person P where P.Id=G.FKUserid and G.FKgroupId=" + Id + " and P.Status=0 order by P.firstName asc
it will disply the username if first name and lastname is there .if there is only firstname .then i won't display any value?....
what is the solution for this ?.in query itself i need to get all the usernames.
with regards
anu
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Rewrite query as
SELECT distinct( COALESEC(P.firstname,P.firstname,'') + ' ' + COALESEC(P.middlename,P.middlename,'') + ' ' + COALESEC(P.lastname,P.lastname,'')) AS UserName ,P.Id as UserId,G.Id,G.Fkgroupid FROM c_Groupmember G,c_Person P where P.Id=G.FKUserid and G.FKgroupId=" + Id + " and P.Status=0 order by P.firstName asc
for more information see COALESCE function documentation.
Intelligence is measured by common sense not by how many scholarly books you read.
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it is showing an error
Msg 195, Level 15, State 10, Line 1
'COALESEC' is not a recognized built-in function name.
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ya.i got .it is 'COALESCE'. Not 'COALESEC'
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anujose wrote: ?.in query itself i need to get all the usernames
Better way of working on queries will be putting them up in a stored proc, to avoid sql injection attacks.[^]
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Try SET CONCAT_NULL_YIELDS_NULL OFF before you begin the query. Works in 2000, not usre about 2005.
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I posted this question before but I'm not sure it was fully understood:
I'm using MSSQL7, NT authentication and application roles so only my application can access the data. Also, other applications (like Excel) can not access the data and read it. So far, so good...
Yet, I noticed that if I try to access the SQL Server from another SQL Server on the network, it is allowed to see the list of tables, SP, etc. It is not allowed to open the table, but the Import/Export wizard is working and will allow retrieving data from the secured tables.
If I change to MSSQL authentication, any user will be able to access the data from my application and I don't want that either.
Unless I'm missing something, this is a big problem, especially today where any VPN connection with valid user name and password can actually log in to the domain and therefore connect to the database via SQL Server.
By the way, the server still must allow access to users via applications so logins must exist. I just don't want other SQL servers on the network to be able to connect to and import/export, view table and SP, etc.
Any ideas?
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you're saying that if a user connects to your DB via the SQL Server tools, they have access to stuff that the role they log in under should not see ?
Christian Graus - Microsoft MVP - C++
"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )
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Correct...
It seems as if any user that can log in to SQL, can use SQL Server to see the list of table, list of SP and import/export data even though their user role does not allow SELECT, UPDATE, INSERT or EXECUTE.
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Hi,
In a table with a primary key and a foreign key like this.
I-------I-------I-------I
I pkey I fkey I name I
I-------I-------I-------I
I 1 I 1 I ITEM I
I-------I-------I-------I
I 2 I 1 I ITEM2 I
I-------i-------I-------I
If we were to run a select query against this table that returns just one row. Would be any performance benefit if we have this select ?:
SELECT * FROM The_Table WHERE pkey=2 AND fkey=1
over when we have this select ?:
SELECT * FROM The_Table WHERE pkey=2
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As the primary key is unique (a condition of being a primary key is that it uniquely identifies the row) then I wouldn't see any need for any additional information in the WHERE clause.
Whether it has any benefit or not depends on how you set up the table. If you go with the traditional defaults then I don't see it having any additional benefit. But I doubt it would have any negative effect either.
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If we define an index on the foreign key field , will be any performance gain ?
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devboycpp wrote: If we define an index on the foreign key field , will be any performance gain ?
In this case, I doubt it. The WHERE clause already contains a reference to a column that is guaranteed to be unique (i.e. the Primary Key) and is most likely to be indexed (unless it was removed) so will go directly to that row. Foreign keys are not normally unique.
Also, adding an index can make performance worse for INSERT, UPDATE and DELETE operations.
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select empid,empname,valid bit null
into #temp
from table
I know this is wrong. What I need is to add a new column which is not in table [valid] and assign that column as bit type and value as null.
Can you please help?
Thanks
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A BIT column is not nullable.
Paul Marfleet
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Please help me this problem, thanks.
Thao
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I'm sorry, I'm sure English is not your first language, and I don't want you to think you're under attack for that. But, your question makes no sense. Your english doesn't have to be perfect, we're very forgiving, but if we don't understand, we just can't hope to help.
Christian Graus - Microsoft MVP - C++
"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )
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I was able to run ssis Installation successfully. In summary of last step, is it possible to take out the author and log file information or rewrite them with other information?
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