6cb1f4fe44
takes two parameters, an OID x and an integer y, and returns "true" with probability 1/y (the OID argument is ignored). This can be useful -- for example, it can be used to select a random sampling of the rows in a table (which is what the "random" regression test uses it for). This patch removes that function, because it was old and messy. The old function had the following problems: - it was undocumented - it was poorly named - it was designed to workaround an optimizer bug that no longer exists (the OID argument is to ensure that the optimizer won't optimize away calls to the function; AFAIK marking the function as 'volatile' suffices nowadays) - it used a different random-number generation technique than the other PSRNG-related functions in the backend do (it called random() like they do, but it had its own logic for setting a set and deciding when to reseed the RNG). Ok, this patch removes oidrand(), oidsrand(), and userfntest(), and improves the SGML docs a little bit (un-commenting the setseed() documentation). Neil Conway
61 lines
1.0 KiB
C
61 lines
1.0 KiB
C
/*-------------------------------------------------------------------------
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*
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* misc.c
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*
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*
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* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/misc.c,v 1.28 2003/02/13 05:24:02 momjian Exp $
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include <sys/file.h>
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#include <time.h>
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#include "miscadmin.h"
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#include "utils/builtins.h"
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/*
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* Check if data is Null
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*/
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Datum
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nullvalue(PG_FUNCTION_ARGS)
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{
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if (PG_ARGISNULL(0))
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PG_RETURN_BOOL(true);
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PG_RETURN_BOOL(false);
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}
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/*
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* Check if data is not Null
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*/
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Datum
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nonnullvalue(PG_FUNCTION_ARGS)
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{
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if (PG_ARGISNULL(0))
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PG_RETURN_BOOL(false);
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PG_RETURN_BOOL(true);
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}
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/*
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* current_database()
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* Expose the current database to the user
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*/
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Datum
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current_database(PG_FUNCTION_ARGS)
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{
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Name db;
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db = (Name) palloc(NAMEDATALEN);
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namestrcpy(db, DatabaseName);
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PG_RETURN_NAME(db);
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}
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