I have SQL query, where I have two parameters and one output parameter (varchar).
How I should call the procedure and get the output parameter?
Thanks.
First of all you have to connect to your db. What technology are you using?
In any case it could be something like that (code is written for c# & Oracle, but it will give you an idea how to solve your case):
IDbConnection dbConnection = new OracleConnection(your_connectionstring)
var param = new OracleDyamicParameters();
param.Add("out_result", OracleDbType.Int64, ParameterDirection.Output);
string query = "Your_proc_Name";
await SqlMapper.QueryAsync<MyReturnClass>(dbConnection, query, param: param, commandType: CommandType.StoredProcedure);
db_res.Result = param.GetOutResult();
Related
I think when I call function DynamicParameter.Add(), Dbtype is not works
I'm using Dapper when I connect to DB. I tried to request query to DB with below code
var parameters = new DynamicParameters();
parameters.Add("#Uid", value: uId, dbType: DbType.string);
var sql = #"select * from User where Uid = #Uid";
The column 'Uid' of 'User' table is type of int. As you saw, I requested query with Uid parameter type of string. I expected it occurred error, however it worked well.
So I'd like to ask. DynamicParameter doesn't check parameter type when add data or run query? If so, why does Dbtype in DynamicParameter.Add() parameter exist?
Thanks in advance
my problem is about this kind of query :
select * from SOMETABLE where SOMEFIELD in ('STRING1','STRING2');
the previous code works fine within Sql Developer.
The same static query also works fine and returns me a few results;
Query nativeQuery = em.createNativeQuery(thePreviousQuery,new someResultSet());
return nativeQuery.getResultList();
But when I try to parameterize this, I encounter a problem.
final String parameterizedQuery = "select * from SOMETABLE where SOMEFIELD in (?selectedValues)";
Query nativeQuery = em.createNativeQuery(parameterizedQuery ,new someResultSet());
nativeQuery.setParameter("selectedValues","'STRING1','STRING2'");
return nativeQuery.getResultList();
I got no result (but no error in console).
And when I look at the log, I see such a thing :
select * from SOMETABLE where SOMEFIELD in (?)
bind => [STRING1,STRING2]
I also tried to use no quotes (with similar result), or non ordered parameter (:selectedValues), which leads to such an error :
SQL Error: Missing IN or OUT parameter at index:: 1
I enventually tried to had the parentheses set directly in the parameter, instead of the query, but this didn't work either...
I could build my query at runtime, to match the first (working) case, but I'd rather do it the proper way; thus, if anyone has an idea, I'll read them with great interest!
FYI :
JPA version 1.0
Oracle 11G
JPA support the use of a collection as a list literal parameter only in JPQL queries, not in native queries. Some JPA providers support it as a proprietary feature, but it's not part of the JPA specification (see https://stackoverflow.com/a/3145275/1285097).
Named parameters in native queries also aren't part of the JPA specification. Their behavior depends on the persistence provider and/or the JDBC driver.
Hibernate with the JDBC driver for Oracle support both of these features.
List<String> selectedValues = Arrays.asList("STRING1", "STRING2");
final String parameterizedQuery = "select * from SOMETABLE where SOMEFIELD in (:selectedValues)";
return em.createNativeQuery(parameterizedQuery)
.setParameter("selectedValues", selectedValues)
.getResultList();
Instead of:
nativeQuery.setParameter("selectedValues", params);
I had to use:
nativeQuery.setParameterList("selectedValues", params);
This worked for me in derby. parameter without "()".
List<String> selectedValues = Arrays.asList("STRING1", "STRING2");
final String parameterizedQuery = "select * from SOMETABLE where SOMEFIELD in
:selectedValues";
return em.createNativeQuery(parameterizedQuery)
.setParameter("selectedValues", selectedValues)
.getResultList();
Replace this:
nativeQuery.setParameter("selectedValues","'STRING1','STRING2'");
with
List<String> params;
nativeQuery.setParameter("selectedValues",params);
I also faced the same issue.
This is what I did:
List<String> sample = new ArrayList<String>();
sample.add("sample1");
sample.add("sample2");
And now you, can set the sample in params.
I never asked any questions on stackoverflow but it already brought me tons of answers !
But this time, after some extended research, I have to ask it myself.
I'm using VB.Net with Sqlite and my query doesn't return any value when I execute it with parameters. I guess this has something to do with the fact SituationString contains commas but I really can't figure it out.
Here's is my code :
dim ChildCtx as Integer
dim SituationString as String
SituationString="968,970,978,979,980,981,995,1022,1099,1119"
With DataBase
.SQL_CMD.Parameters.Clear()
.SQL_CMD.CommandText = "SELECT SERVCTX_NO FROM SERVCTX WHERE SERVCTX_NO IN (#situationstring) AND MASTER = '1'"
.SQL_CMD.Parameters.Add("#situationstring", SqlDbType.VarChar, 255).Value = SituationString
ChildCtx = .SQL_CMD.ExecuteScalar
.SQL_CMD.Parameters.Clear()
End with
Connection is open and query works out fine if I write the whole query into one string.
Thanks,
You are mixing two techincs: merging constant data into SQL command and using parameters to pass data.
I suppose SituationString is a list of integer you expect for SERVCTX_NO.
So, you must merge it into statement:
.SQL_CMD.CommandText = "SELECT SERVCTX_NO FROM SERVCTX WHERE SERVCTX_NO IN ("+SituationString+") AND MASTER = '1'"
ChildCtx = .SQL_CMD.ExecuteScalar
Using parameters, as you did, SERVCTX_NO would be expected to be a string with 968,970,978,979,980,981,995,1022,1099,1119 exact content!
I have just started using LinqPad:
var con1 = from con in table
where con.tableKey == Guid.Parse("8EA5DC2C-2603-499A-A9D3-00019B53421F")
select con;
con.Dump();
throws me error
") or end of expression expected (change the Query Language to 'C# Statements' for multi-statement queries)"
Can anyone please correct me?
And also i have notices File-> New Query, New Query same properties on linqpad.
What is the difference between them? Thanks.
Make sure your type of query is C# statements and not C# expression... but if you aren't doing more than 1 statement you don't need the con.Dump(); (I think)
I simply want to include a row number against the returned results of my query.
I found the following post that describes what I am trying to achieve but gives me an exception
http://vaultofthoughts.net/LINQRowNumberColumn.aspx
"An expression tree may not contain an assignment operator"
In MS SQL I would just use the ROWNUMBER() function, I'm simply looking for the equivalent in LINQ.
Use AsEnumerable() to evaluate the final part of your query on the client, and in that final part add a counter column:
int rowNo = 0;
var results = (from data in db.Data
// Add any processing to be performed server side
select data)
.AsEnumerable()
.Select(d => new { Data = d, Count = ++rowNo });
I'm not sure whether LINQ to SQL supports it (but it propably will), but there's an overload to the Queryable.Select method that accepts an lambda with an indexer. You can write your query as follows:
db.Authors.Select((author, index) => new
{
Lp = index, Name = author.Name
});
UPDATE:
I ran a few tests, but unfortunately LINQ to SQL does not support this overload (both 3.5sp1 and 4.0). It throws a NotSupportedException with the message:
Unsupported overload used for query
operator 'Select'.
LINQ to SQL allows you to map a SQL function. While I've not tested this, I think this construct will work:
public partial class YourDataContext : DatContext
{
[Function(Name = "ROWNUMBER")]
public int RowNumber()
{
throw InvalidOperationException("Not called directly.");
}
}
And write a query as follows:
from author in db.Authors
select new { Lp = db.RowNumber(), Name = author.Name };