XMLTABLE by example, Part 1: Retrieving XML data in relational format
Using a default namespace only allows you to select elements and attributes from that namespace, and using a wildcard selects elements and attributes from all namespaces. Part 2 describes common XMLTABLE usage scenarios such as XML shredding, splitting large documents into smaller ones, and relational views over XML data
PostgreSQL: Documentation: 8.4: CREATE FUNCTION
The key word EXTERNAL is allowed for SQL conformance, but it is optional since, unlike in SQL, this feature applies to all functions not only external ones. (When using OUT parameters, that means you cannot change the names or types of any OUT parameters except by dropping the function.) If you drop and then recreate a function, the new function is not the same entity as the old; you will have to drop existing rules, views, triggers, etc
I even try to avoid hard-coding Y in my Oracle Application Express code.) By moving this logic to my packaged function, I not only greatly clean up the logic on page 659 and reduce the chance of introducing bugs in the future but I also increase the percentage of reusable code in my application. The downside of 100 percent coding for applications is that developers are generally much less productive and the resulting code is much less structured than application code developed with a RAD framework, such as Oracle Application Express (or Oracle JDeveloper)
What this actually means is that we can create a set of processing rules inside one or more object types and "plug them into" the Oracle server to use in various scenarios. We store the cursor information in a package variable for sharing across methods; fetch: using the cursor description and ANYTYPE metadata, we fetch data off the dynamic SQL cursor into a relevant type variable
Here are a few more differences between a procedure and a function: A function MUST return a value A procedure cannot return a value Procedures and functions can both return data in OUT and IN OUT parameters The return statement in a function returns control to the calling program and returns the results of the function The return statement of a procedure returns control to the calling program and cannot return a value Functions can be called from SQL, procedure cannot Functions are considered expressions, procedure are not That's about all the differences I can think of off the top of my head. am very keen on learning.will you please help me learn it from the sratch.Im very keen on learning the database and expanding my knowledge.Are there any docs, links,materials where I can self learn.Need your help.Thanks a lot
The article is intended for SQL coders, who for might be not be using analytic functions due to unfamiliarity with its cryptic syntax or uncertainty about its logic of operation. What about when you have a data set that contains records with timestamps and you would like to roll them up to the second and then look at a sliding window to find, say the busiest 5 minutes of the day? It is trivial to create the query to aggregate the data into per-second blocks but I cannot figure out the syntax to put a window around it
Shuttle the methods to selected area and Click OK - Open the JSF page and expand the data control - Drag the logProcedure Method to the page and choose ADF button - Drag the getEmpFullname function to the page and choose ADF parameter form (it is a function so we have to bind the input and return values) -Drag and drop the String (output parameter) as Output Text - The page on design time look like this - Right click and choose Run . If we analyze that this code can work inside database so we should move it to database and if the logic depends on some UI interaction (e.g looping over the rows etc etc) then it should be the combination of both
Whatever method we use, however, the statistics we generate can help the CBO to decide predicate and join orders, although complex query transformations are out of scope. We will now replace the default statistics with an interface type to more accurately calculate costs and selectivities for different promotion categories
Since I must treat a response, I have tried the third situation explained in this article, but I get an error in ODI which says that the identifier must be declared. Please feel free if you have any other question Reply Cezar Santos April 29, 2010 at 6:57 AM Hi Jay, Yes, you can handle multiple out parameters by creating multiples functions
See Also: "Subprogram Parameter Aliasing with Parameters Passed by Reference" In Example 12-18, the intention is to select specific values from a collection, numbers1, and then store them in the same collection. However, because the compiler inlines subprograms early in the optimization process, it is possible for subprogram inlining to preclude later, more powerful optimizations
The SQL executed by a slave scan process is similar to: SELECT f(col1) FROM tab WHERE ROWID BETWEEN :b1 AND :b2; Each slave scan operates on a range of rowids and applies function f to each contained row. The closest match is one where all the parameters are at least as close as any other overloaded instance, as determined by the depth of inheritance between the subtype and supertype, and at least one parameter is closer
RETURN; statement 2; END; In the above syntax, when the execution pointer comes to the RETURN statement, Oracle skips all subsequent statements and returns to the calling environment. As soon as it is encountered in the subprogram body, Oracle server immediately sends the execution control back to the immediate calling code or host environment
No comments:
Post a Comment