Dapper parameters not working? - dapper

Dapper 1.34 (on earlier Dapper ver like 1.1x this worked fine).
db.Query(#"Select [whatever] from #TableName Where [PREFIX]='#Prefix' order by [something] desc",
new { TableName = tableName, Prefix = prefix })
Error: System.Data.SqlClient.SqlException (0x80131904): Must declare the table variable "#TableName".
I get same error trying to define DynamicParameters and passing those.
=======
I am currently doing string substitution {%1} .. but that does not seem acceptable ...
Can I please get a sample, also looking at test class for dapper I cant see it running, maybe something wrong with my project setup ?

No, that has never worked fine, due to how SQL works:
table names cannot be parameterized, and dapper has never offered this; that could work if you pass in a DataTable as a table-valued-parameter, though - which dapper does support - but I don't think this is what you are after
'#Prefix' is a string literal; you just mean #Prefix (no single quotes)

Related

Django model based on an SQL table-valued function using MyModel.objects.raw()

If it's relevant I'm using Django with Django Rest Framework, django-mssql-backend and pyodbc
I am building some read only models of a legacy database using fairly complex queries and Django's MyModel.objects.raw() functionality. Initially I was executing the query as a Select query which was working well, however I received a request to try and do the same thing but with a table-valued function from within the database.
Executing this:
MyModel.objects.raw(select * from dbo.f_mytablefunction)
Gives the error: Invalid object name 'myapp_mymodel'.
Looking deeper into the local variables at time of error it looks like this SQL is generated:
'SELECT [myapp_mymodel].[Field1], '
'[myapp_mymodel].[Field2] FROM '
'[myapp_mymodel] WHERE '
'[myapp_mymodel].[Field1] = %s'
The model itself is mapped properly to the query as executing the equivalent:
MyModel.objects.raw(select * from dbo.mytable)
Returns data as expected, and dbo.f_mytablefunction is defined as:
CREATE FUNCTION dbo.f_mytablefunction
(
#param1 = NULL etc etc
)
RETURNS TABLE
AS
RETURN
(
SELECT
field1, field2 etc etc
FROM
dbo.mytable
)
If anyone has any explanation as to why these two modes of operation are treated substantially differently then I would be very pleased to find out.
Guess you've figured this out by now (see docs):
MyModel.objects.raw('select * from dbo.f_mytablefunction(%s)', [1])
If you'd like to map your table valued function to a model, this gist has a quite thorough approach, though no license is mentioned.
Once you've pointed your model 'objects' to the new TableFunctionManager and added the 'function_args' OrderedDict (see tests in gist), you can query it as follows:
MyModel.objects.all().table_function(param1=1)
For anyone wondering about use cases for table valued functions, try searching for 'your_db_vendor tvf'.

'do_replace()' not working?

while trying ATK4 I've found a problem:
$this->api->db->dsql()->table('person')->set('id', 1)->set('name', 'Test user')->do_replace();
This is not working. Then I looked a little bit deeper in ATK4 source and found in /opt/ipism/www/atk4/lib/DB/dsql.php the lines
public $sql_templates=array(
'select'=>"select [options] [field] [from] [table] [join] [where] [group] [having] [order] [limit]",
'insert'=>"insert [options_insert] into [table_noalias] ([set_fields]) values ([set_values])",
'replace'=>"replace [options_replace] into [table_noalias] ([set_fields]) values ([set_values])",
'update'=>"update [table_noalias] set [set] [where]",
'delete'=>"delete from [table_noalias] [where]",
'truncate'=>'truncate table [table_noalias]',
'describe'=>'desc [table_noalias]',
);
After changing the 'replace'-line into
'replace'=>"replace into [table_noalias] ([set_fields]) values ([set_values])",
it worked for me (removing the options_replace and appending a 's' to set_value). I'm using latest version from git with a MySQL database connection.
But I'm not sure, if I'm using 'do-replace()' in the wrong way?
ByE...
By the way: Is there a way to send fixes, without creating an account on GitHub or somewhere?
Edit: Here is the output if the options_replace isn't removed from the template:
replace [options_replace] into `person` (`id`,`name`) values ("1","John Doe") [:a_2, :a]Application Error: Database Query Failed
Exception_DB, code: 0Additional information: pdo_error: SQLSTATE[42000]: Syntax error or access violation: 1064 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 '[options_replace] into `person` (`id`,`name`) values ('1' at line 1 mode: replace params: :a: 1 :a_2: John Doe query: replace [options_replace] into `person` (`id`,`name`) values (:a,:a_2) template: replace [options_replace] into [table_noalias] ([set_fields]) values ([set_values])/opt/ipism/www/atk4/lib/DB/dsql.php:1519
Stack trace:
File Object NameStack Trace/opt/ipism/www/atk4/lib/BaseException.php:63 Exception_DBException_DB->collectBasicData(Null)
/opt/ipism/www/atk4/lib/AbstractObject.php:545 Exception_DBException_DB->__construct("Database Query Failed", Null)
/opt/ipism/www/atk4/lib/DB/dsql.php:1519 sample_project_db_db_dsql_mysqlDB_dsql_mysql->exception("Database Query Failed")
/opt/ipism/www/atk4/lib/DB/dsql.php:1586 sample_project_db_db_dsql_mysqlDB_dsql_mysql->execute()
/opt/ipism/www/atk4/lib/DB/dsql.php:1624 sample_project_db_db_dsql_mysqlDB_dsql_mysql->replace()
/opt/ipism/www/page/test.php:40 sample_project_db_db_dsql_mysqlDB_dsql_mysql->do_replace()
/opt/ipism/www/atk4/lib/AbstractObject.php:306 sample_project_testpage_test->init()
/opt/ipism/www/atk4/lib/ApiFrontend.php:130 sample_projectFrontend->add("page_test", "test", "Content")
/opt/ipism/www/atk4/lib/ApiWeb.php:428 sample_projectFrontend->layout_Content()
/opt/ipism/www/atk4/lib/ApiFrontend.php:39 sample_projectFrontend->addLayout("Content")
/opt/ipism/www/atk4/lib/ApiWeb.php:275 sample_projectFrontend->initLayout()
/opt/ipism/www/index.php:15 sample_projectFrontend->main()
Note: To hide this information from your users, add $config['logger']['web_output']=false to your config.php file. Refer to documentation on 'Logger' for alternative logging options
Replace is similar to "insert" by it's nature, but instead of failing when primary key is duplicated, it replaces the value.
Please add ->debug() to your line before do_replace and give me the output, which would help me understand why that parameter needs removing.
set_value seems to be a typo, I have changed and committed it into master: https://github.com/atk4/atk4/commit/24b20865b9e3345a8e7504dfb68b7ef96335009e
the best way to submit changes is by creating a pull request. The best way to report issues is through "issues" in github currently.

How to pass a string literal parameter to a peewee fn call

I've got a issue passing a string literal parameter to a SQL function using peewee's fn construct. I've got an object defined as:
class User(BaseModel):
computingID = CharField()
firstName = CharField()
lastName = CharField()
role = ForeignKeyField(Role)
lastLogin = DateTimeField()
class Meta:
database = database
I'm attempting to use the mySQL timestampdiff function in a select to get the number of days since the last login. The query should look something like this:
SELECT t1.`id`, t1.`computingID`, t1.`firstName`, t1.`lastName`, t1.`role_id`, t1.`lastLogin`, timestampdiff(day, t1.`lastLogin`, now()) AS daysSinceLastLogin FROM `user` AS t1
Here's the python peewee code I'm trying to use:
bob = User.select(User, fn.timestampdiff('day', User.lastLogin, fn.now()).alias('daysSinceLastLogin'))
result = bob[0].daysSinceLastLogin
But when I execute this code, I get an error:
ProgrammingError: (1064, u"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 ''day', t1.lastLogin, now()) AS
daysSinceLastLogin FROM user AS t1' at line 1")
Judging from this message, it looks like the quote marks around the 'day' parameter are being retained in the SQL that peewee is generating. And mySQL doesn't like quotes around the parameter. I obviously can't leave off the quotes in the python code, so can someone tell me what I'm doing wrong please?
Update: I have my query working as intended by using the SQL() peewee command to add the DAY parameter, sans quote marks:
User.select(User, fn.timestampdiff(SQL('day'), User.lastLogin, fn.now()).alias('daysSinceLastLogin'))
But I'm not sure why I had to use SQL() in this situation. Am I missing anything, or is this the right answer?
Is there a reason you need to use an SQL function to do this?
In part because I'm not very comfortable with SQL functions, I would probably do something like this:
import datetime as dt
bob = user.get(User = "Bob") #or however you want to get the User instance
daysSinceLastLogin = (dt.datetime.now() - bob.lastLogin).days

DB2 -- How to use LTRIM scalar function with 2 arguments?

I am new to DB2 (using version 10.1) and I'm trying to execute a simple ltrim function in a test query.
select ltrim(',1,2,3,4', ',') from sysibm.sysdummy1;
This results in the following error:
DB2 SQL Error: SQLCODE=-440, SQLSTATE=42884, SQLERRMC=LTRIM;FUNCTION, DRIVER=3.65.77
Based on the documentation here, it seems my example should work. Note, I can use the alternative trim function or the 1-arg version of ltrim:
select trim(l ',' from ',1,2,3,4') from sysibm.sysdummy1;
select ltrim(' test') from sysibm.sysdummy1;
And those works fine!
Are there some fundamental differences between the 2-arg form of ltrim and the other examples I provided?
This function was added in DB2 10.1 fix pack 2 -- you may want to upgrade.
Making some guesses here, but are you sure you're on 10.1? That version of that function you're trying to use appears to have been added in 10, so if you're on 9.x, it won't work.
If you are, you might check and see if your schema path includes SYSIBM:
SELECT CURRENT_PATH FROM SYSIBM.SYSDUMMY1
The "old" one-argument version of the function is in SYSFUN, which (if your path doesn't include SYSIBM) might be why you're still able to use that version.
If SYSIBM isn't in your path, you can try changing it using:
SET PATH = SYSIBM, CURRENT_PATH
Why not try STRIP() instead:
VALUES STRIP(',1,2,3,4', L, ',');
(side note: It is simpler to use the VALUES statement, rather than SELECT FROM SYSIBM.SYSDUMMY1)

Is it possible to create table-valued *methods* in a SQL CLR user-defined type?

I have a CLR UDT that would benefit greatly from table-valued methods, ala xml.nodes():
-- nodes() example, for reference:
declare #xml xml = '<id>1</id><id>2</id><id>5</id><id>10</id>'
select c.value('.','int') as id from #xml.nodes('/id') t (c)
I want something similar for my UDT:
-- would return tuples (1, 4), (1, 5), (1, 6)....(1, 20)
declare #udt dbo.FancyType = '1.4:20'
select * from #udt.AsTable() t (c)
Does anyone have any experience w/ this? Any help would be greatly appreciated. I've tried a few things and they've all failed. I've looked for documentation and examples and found none.
Yes, I know I could create table-valued UDFs that take my UDT as a parameter, but I was rather hoping to bundle everything inside a single type, OO-style.
EDIT
Russell Hart found the documentation states that table-valued methods are not supported, and fixed my syntax to produce the expected runtime error (see below).
In VS2010, after creating a new UDT, I added this at the end of the struct definition:
[SqlMethod(FillRowMethodName = "GetTable_FillRow", TableDefinition = "Id INT")]
public IEnumerable GetTable()
{
ArrayList resultCollection = new ArrayList();
resultCollection.Add(1);
resultCollection.Add(2);
resultCollection.Add(3);
return resultCollection;
}
public static void GetTable_FillRow(object tableResultObj, out SqlInt32 Id)
{
Id = (int)tableResultObj;
}
This builds and deploys successfully. But then in SSMS, we get a runtime error as expected (if not word-for-word):
-- needed to alias the column in the SELECT clause, rather than after the table alias.
declare #this dbo.tvm_example = ''
select t.[Id] as [ID] from #this.GetTable() as [t]
Msg 2715, Level 16, State 3, Line 2
Column, parameter, or variable #1: Cannot find data type dbo.tvm_example.
Parameter or variable '#this' has an invalid data type.
So, it seems it is not possible after all. And even if were possible, it probably wouldn't be wise, given the restrictions on altering CLR objects in SQL Server.
That said, if anyone knows a hack to get around this particular limitation, I'll raise a new bounty accordingly.
You have aliased the table but not the columns. Try,
declare #this dbo.tvm_example = ''
select t.[Id] as [ID] from #this.GetTable() as [t]
According to the documentation, http://msdn.microsoft.com/en-us/library/ms131069(v=SQL.100).aspx#Y4739, this should fail on another runtime error regarding incorrect type.
The SqlMethodAttribute class inherits from the SqlFunctionAttribute class, so SqlMethodAttribute inherits the FillRowMethodName and TableDefinition fields from SqlFunctionAttribute. This implies that it is possible to write a table-valued method, which is not the case. The method compiles and the assembly deploys, but an error about the IEnumerable return type is raised at runtime with the following message: "Method, property, or field '' in class '' in assembly '' has invalid return type."
They may be avoiding supporting such a method. If you alter the assembly with method updates this can cause problems to the data in UDT columns.
An appropriate solution is to have a minimal UDT, then a seperate class of methods to accompany it. This will ensure flexibility and fully featured methods.
xml nodes method will not change so it is not subject to the same implemetation limitations.
Hope this helps Peter and good luck.

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