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(materialization into a tuple store) discussed on pgsql-hackers earlier. I've updated the documentation and the regression tests. Notes on the implementation: - I needed to change the tuple store API slightly -- it assumes that it won't be used to hold data across transaction boundaries, so the temp files that it uses for on-disk storage are automatically reclaimed at end-of-transaction. I added a flag to tuplestore_begin_heap() to control this behavior. Is changing the tuple store API in this fashion OK? - in order to store executor results in a tuple store, I added a new CommandDest. This works well for the most part, with one exception: the current DestFunction API doesn't provide enough information to allow the Executor to store results into an arbitrary tuple store (where the particular tuple store to use is chosen by the call site of ExecutorRun). To workaround this, I've temporarily hacked up a solution that works, but is not ideal: since the receiveTuple DestFunction is passed the portal name, we can use that to lookup the Portal data structure for the cursor and then use that to get at the tuple store the Portal is using. This unnecessarily ties the Portal code with the tupleReceiver code, but it works... The proper fix for this is probably to change the DestFunction API -- Tom suggested passing the full QueryDesc to the receiveTuple function. In that case, callers of ExecutorRun could "subclass" QueryDesc to add any additional fields that their particular CommandDest needed to get access to. This approach would work, but I'd like to think about it for a little bit longer before deciding which route to go. In the mean time, the code works fine, so I don't think a fix is urgent. - (semi-related) I added a NO SCROLL keyword to DECLARE CURSOR, and adjusted the behavior of SCROLL in accordance with the discussion on -hackers. - (unrelated) Cleaned up some SGML markup in sql.sgml, copy.sgml Neil Conway |
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| backendid.h | ||
| block.h | ||
| buf.h | ||
| buf_internals.h | ||
| buffile.h | ||
| bufmgr.h | ||
| bufpage.h | ||
| fd.h | ||
| freespace.h | ||
| ipc.h | ||
| item.h | ||
| itemid.h | ||
| itempos.h | ||
| itemptr.h | ||
| large_object.h | ||
| lmgr.h | ||
| lock.h | ||
| lwlock.h | ||
| off.h | ||
| page.h | ||
| pg_sema.h | ||
| pg_shmem.h | ||
| pmsignal.h | ||
| pos.h | ||
| proc.h | ||
| relfilenode.h | ||
| s_lock.h | ||
| shmem.h | ||
| sinval.h | ||
| sinvaladt.h | ||
| smgr.h | ||
| spin.h | ||