I have to define a JPA call to a stored procedure that returns unnamed columns.
Is there a way to define a SqlResultSetMapping or Entity object that does not require to name column results but reads the result by index ?
The result from the stored procedure looks something like this:
One
Two
Three
Related
My database is structured with a schema per application user. In each schema there is an identical table named "entries" with the exact same DDL. I also have a common schema that hosts some functions that operate on those "entries" tables, and during execution the search path defines which schema's entries table the function operates on. I had a problem defining those functions before i create any user schema because they reference the non yet created tables in the user schemata. That problem was solved using set check_function_bodies = off; But now I have a similar problem with a function that references those tables as an inout parameter. I cannot create that function because a parameter that it accepts is of type "entries" and I get an error of "type entries does not exist". set check_function_bodies = off does not solve this problem. Is there a way to solve this problem?
The function signature is
create or replace function common.reconcile_user_entry(inout e entries) returns void
I really dont want to define this function in each user schema as it will always be the same, and i dont want to have to recompile it in every schema when I need to make a change.
You could use inheritance for that.
Define a table common.entries just like all other entries tables and change the other entries tables to inherit from it:
ALTER TABLE schema1.entries INHERIT common.entries;
Then define the function to have common.entries as parameter or return type, and you can use it with any of the inherited tables.
I think you could use table inheritance.
You would have to create a "parent" table in common schema for every table you have in users schema. Then inherit users tables from them. Use "parent" table names when defining function parameters. See example:
CREATE TABLE parent(id integer);
CREATE TABLE child() INHERITS (parent);
INSERT INTO child(id) VALUES (1);
CREATE FUNCTION get_id(IN prm_row parent) RETURNS integer
LANGUAGE SQL
AS $$
SELECT prm_row.id;
$$;
SELECT get_id((SELECT (child) FROM child WHERE id = 1));
Note, that parent table will containt the records from all the child tables, so you should use permission to prevent users accessing the parent tables.
Instead of going with inheritance I ended up solving it by circumventing the problem like this:
Instead of defining the function signature as
create or replace function common.reconcile_user_entry(inout e entries) returns void
I defined it as
create or replace function common.reconcile_user_entry(inout r record) returns void
and in the function code I declare a variable e entries; and then assign the record into the variable:
declare
e entries;
begin
select into e r.*
...
Regarding the inheritance solution, it works, but I found the above solution much simpler.
I know there must be caveats and hidden problems with my solution, if someone can point, please do.
I need to modify the generated SQL for insert/update operation, before it is sent to database. The required modification is very specific, so I was hoping that there is a way to simply append string to statement.
For example, SQL looks like this (Oracle BTW):
UPDATE TABLE_A
SET DESCRIPTION = "ABC"
WHERE OBJECTID = 1
But I want to append this line (in SET part) to update one more field:
SHAPE = sde.st_geometry('point (18 57)', 4326)
I can't add SHAPE column to EF model, because that is unsupported data type.
Now, is there a way I can modify EF generated SQL statement?
You could move this update to a simple stored procedure that is mapped into your entity data model.
I have about 20 (and there will be more) specific stored procedures in my PostgreSQL 9.2 DB. They are used to make some calculations, some kind of financial "reports" (unfortunately, I can't just store data in tables and implement algorithms in the programs's code).
Procedures are very different one from another, they're operating on different tables, columns, implementing different algorithms etc.
Every procedure returns the same data type (numeric value).
And now, my client wants to create the funcionality, where user can select specific procedure (or combination of them, e.g. 10% of procedure's 1 returning value + 90% of procedure's 2 returning value), and use it as a "base" for later modeling.
He wants also my user to be able to change his selection later, without calling programmers every time. ;-)
I thought about making some tables:
Table: base_models
id <PK>,
user_id, <FK from users table>
model_name (varchar, or sth.)
Table: base_models_algorithms
base_model_id <FK from base_models>
algorithm_id <FK from algorithms>
percent_value (percent value of specific algorithm in model, eg. 10)
...and then, I need to store also my algorithm names (= stored procedures) in some table:
Table: algorithms
name: (stored procedure name, varchar?)
... and that's where the problem is.
Of course I can later create some view, with a column calculated by another procedure (model_current_value :-)), and decide what procedure to call depending on name stored in my algorithm's table, but that look awful for me. :(
There would be no data control (you can write anything to algorithms' table, and there is no way to ensure that this string is a name of procedure, returning correct data type etc.).
Of course I can fill the table myself, and won't let anyone to change it's data :-)
But maybe there is more elegant way to do the whole thing?
It sounds like you want the PL/PgSQL EXECUTE statement. You can use this to invoke dynamic SQL, eg for a 2-argument procedure with dynamic name:
EXECUTE format('SELECT %I($1,$2)', func_name) USING arg1, arg2;
This is a PL/PgSQL statement. It is not available in regular SQL. You can of course create a simple PL/PgSQL procedure that does this statement and call that from SQL.
I have a stored procedure that grabs data recursively. I did a function import in my entity set. I can create a function in my ObjectContext that looks like this:
public ObjectResult<ProviderAccountSetting> GetProviderAccountSettings(long providerAccountId)
{
string functionName = "MyContainer.GetProviderAccountSettings";
ObjectParameter providerAccountIdParameter = new ObjectParameter("providerAccountId", providerAccountId);
ObjectResult<ProviderAccountSetting> results = context.ExecuteFunction<ProviderAccountSetting>(functionName, providerAccountIdParameter);
return results;
}
However, I cannot perform a join with LINQ without getting an error. Is there a way to tell Entity Framework to use the stored procedure whenever I access an entity? I would like my stored procedure to be used any time I grab data for that entity. Furthermore, I want it to work with joins. Does Entity Framework support this type of stored-procedure to table mapping? Otherwise, is there a way to join a function import?
Neither of your requirement is possible. You cannot tell EF to use stored procedure every time when you query data. You must manually call your GetProviderAccountSettings to call stored procedure. You also cannot use join (on database side) when using stored procedures (it is even not possible in SQL directly). If you need to join any data to result set of your stored procedure it must be done directly in the procedure and returned as result set. Otherwise you must execute your stored procedure and joined query separately and join them in linq-to-objects.
I have a stored procedure that returns the temporary table data. because i have used dynamic queries. When i tried to map stored procedure using complex types it returns no columns
how to handle temporary table columns name in complex types?
It is not supported by default because EF always executes SET FMTONLY ON before executing your stored procedure. This option will turn off logic execution - it will only ask for metadata but if logic execution is turned off no temporary table is created and no column's metadata exists.
There are some workarounds.