是否可以遍历 Oracle 中的 rowtype 字段？

Question

Say i have something like this:

somerecord SOMETABLE%ROWTYPE;

Is it possible to access the fields of somerecord with out knowing the fields names? Something like somerecord[i] such that the order of fields would be the same as the column order in the table?

I have seen a few examples using dynamic sql but i was wondering if there is a cleaner way of doing this.

What i am trying to do is generate/get the DML (insert query) for a specific row in my table but i havent been able to find anything on this.

If there is another way of doing this i'd be happy to use but would also be very curious in knowing how to do the former part of this question - it's more versatile.

Thanks

Answer 1

This doesn't exactly answer the question you asked, but might get you the result you want...

You can query the USER_TAB_COLUMNS view (or the other similar *_TAB_COLUMN views) to get information like the column name (COLUMN_NAME), position (COLUMN_ID), and data type (DATA_TYPE) on the columns in a table (or a view) that you might use to generate DML.

You would still need to use dynamic SQL to execute the generated DML (or at least generate static SQL separately).

However, this approach won't work for identifying the columns in an arbitrary query (unless you create a view of it). If you need that, you might need to resort to DBMS_SQL (or other tools).

Hope this helps.

Answer 2

As far as I know there is no clean way of referencing record fields by their index.

However, if you have a lot of different kinds of updates of the same table each with its own column set to update, you might want to avoid dynamic sql and look in the direction of statically populating your record with values, and then issuing update someTable set row = someTableRecord where someTable.id = someTableRecord.id; .

This approach has it's own drawbacks, like, issuing an update to every, even unchanged column, and thus creating additional redo log data, but I believe it should be considered.