From d2c744aa56aca7fe756a156a8e2109aaa676e54f Mon Sep 17 00:00:00 2001
From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Fri, 8 Nov 2002 17:37:52 +0000
Subject: [PATCH] Add extra_float_digits GUC parameter to allow adjustment of
displayed precision for float4, float8, and geometric types. Set it in
pg_dump so that float data can be dumped/reloaded exactly (at least on
platforms where the float I/O support is properly implemented). Initial
patch by Pedro Ferreira, some additional work by Tom Lane.
---
doc/src/sgml/runtime.sgml | 26 ++++++++++++-
src/backend/utils/adt/float.c | 31 +++++++++++----
src/backend/utils/adt/geo_ops.c | 39 ++++++++++++-------
src/backend/utils/misc/guc.c | 7 +++-
src/backend/utils/misc/postgresql.conf.sample | 3 +-
src/bin/pg_dump/pg_dump.c | 31 ++++++++++-----
src/bin/psql/tab-complete.c | 3 +-
src/include/utils/builtins.h | 4 +-
8 files changed, 106 insertions(+), 38 deletions(-)
diff --git a/doc/src/sgml/runtime.sgml b/doc/src/sgml/runtime.sgml
index 25a39862042..c5718040fcb 100644
--- a/doc/src/sgml/runtime.sgml
+++ b/doc/src/sgml/runtime.sgml
@@ -1,5 +1,5 @@
<!--
-$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.148 2002/11/05 23:16:56 momjian Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.149 2002/11/08 17:37:52 tgl Exp $
-->
<Chapter Id="runtime">
@@ -1448,6 +1448,30 @@ dynamic_library_path = '/usr/local/lib/postgresql:/home/my_project/lib:$libdir'
</listitem>
</varlistentry>
+ <varlistentry>
+ <indexterm>
+ <primary>significant digits</primary>
+ </indexterm>
+ <indexterm>
+ <primary>display</primary>
+ <secondary>of float numbers</secondary>
+ </indexterm>
+
+ <term><varname>EXTRA_FLOAT_DIGITS</varname> (<type>integer</type>)</term>
+ <listitem>
+ <para>
+ This parameter adjusts the number of digits displayed for
+ floating-point values, including <type>float4</>, <type>float8</>,
+ and geometric datatypes. The parameter value is added to the
+ standard number of digits (<literal>FLT_DIG</> or <literal>DBL_DIG</>
+ as appropriate). The value can be set as high as 2, to include
+ partially-significant digits; this is especially useful for dumping
+ float data that needs to be restored exactly. Or it can be set
+ negative to suppress unwanted digits.
+ </para>
+ </listitem>
+ </varlistentry>
+
<varlistentry>
<term><varname>KRB_SERVER_KEYFILE</varname> (<type>string</type>)</term>
<listitem>
diff --git a/src/backend/utils/adt/float.c b/src/backend/utils/adt/float.c
index fa34e105c15..c0acc554b8e 100644
--- a/src/backend/utils/adt/float.c
+++ b/src/backend/utils/adt/float.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/adt/float.c,v 1.82 2002/10/19 02:08:17 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/adt/float.c,v 1.83 2002/11/08 17:37:52 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -94,9 +94,6 @@ extern double rint(double x);
#endif /* NeXT check */
-static void CheckFloat4Val(double val);
-static void CheckFloat8Val(double val);
-
#ifndef M_PI
/* from my RH5.2 gcc math.h file - thomas 2000-04-03 */
#define M_PI 3.14159265358979323846
@@ -113,8 +110,6 @@ static void CheckFloat8Val(double val);
#define SHRT_MIN (-32768)
#endif
-#define FORMAT 'g' /* use "g" output format as standard
- * format */
/* not sure what the following should be, but better to make it over-sufficient */
#define MAXFLOATWIDTH 64
#define MAXDOUBLEWIDTH 128
@@ -128,6 +123,14 @@ static void CheckFloat8Val(double val);
#define FLOAT8_MIN DBL_MIN
+/* Configurable GUC parameter */
+int extra_float_digits = 0; /* Added to DBL_DIG or FLT_DIG */
+
+
+static void CheckFloat4Val(double val);
+static void CheckFloat8Val(double val);
+
+
/*
* check to see if a float4 val is outside of
* the FLOAT4_MIN, FLOAT4_MAX bounds.
@@ -228,6 +231,7 @@ float4out(PG_FUNCTION_ARGS)
float4 num = PG_GETARG_FLOAT4(0);
char *ascii = (char *) palloc(MAXFLOATWIDTH + 1);
int infflag;
+ int ndig;
if (isnan(num))
PG_RETURN_CSTRING(strcpy(ascii, "NaN"));
@@ -237,7 +241,12 @@ float4out(PG_FUNCTION_ARGS)
if (infflag < 0)
PG_RETURN_CSTRING(strcpy(ascii, "-Infinity"));
- sprintf(ascii, "%.*g", FLT_DIG, num);
+ ndig = FLT_DIG + extra_float_digits;
+ if (ndig < 1)
+ ndig = 1;
+
+ sprintf(ascii, "%.*g", ndig, num);
+
PG_RETURN_CSTRING(ascii);
}
@@ -290,6 +299,7 @@ float8out(PG_FUNCTION_ARGS)
float8 num = PG_GETARG_FLOAT8(0);
char *ascii = (char *) palloc(MAXDOUBLEWIDTH + 1);
int infflag;
+ int ndig;
if (isnan(num))
PG_RETURN_CSTRING(strcpy(ascii, "NaN"));
@@ -299,7 +309,12 @@ float8out(PG_FUNCTION_ARGS)
if (infflag < 0)
PG_RETURN_CSTRING(strcpy(ascii, "-Infinity"));
- sprintf(ascii, "%.*g", DBL_DIG, num);
+ ndig = DBL_DIG + extra_float_digits;
+ if (ndig < 1)
+ ndig = 1;
+
+ sprintf(ascii, "%.*g", ndig, num);
+
PG_RETURN_CSTRING(ascii);
}
diff --git a/src/backend/utils/adt/geo_ops.c b/src/backend/utils/adt/geo_ops.c
index 68917a64d60..ddad1225851 100644
--- a/src/backend/utils/adt/geo_ops.c
+++ b/src/backend/utils/adt/geo_ops.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/adt/geo_ops.c,v 1.66 2002/09/05 00:43:07 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/adt/geo_ops.c,v 1.67 2002/11/08 17:37:52 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -19,6 +19,7 @@
#include <float.h>
#include <ctype.h>
+#include "utils/builtins.h"
#include "utils/geo_decls.h"
#ifndef PI
@@ -79,11 +80,9 @@ static Point *line_interpt_internal(LINE *l1, LINE *l2);
#define LDELIM_C '<'
#define RDELIM_C '>'
-/* Maximum number of output digits printed */
-#define P_MAXDIG DBL_DIG
-#define P_MAXLEN (2*(P_MAXDIG+7)+1)
-
-static int digits8 = P_MAXDIG;
+/* Maximum number of characters printed by pair_encode() */
+/* ...+2+7 : 2 accounts for extra_float_digits max value */
+#define P_MAXLEN (2*(DBL_DIG+2+7)+1)
/*
@@ -139,7 +138,12 @@ single_decode(char *str, float8 *x, char **s)
static int
single_encode(float8 x, char *str)
{
- sprintf(str, "%.*g", digits8, x);
+ int ndig = DBL_DIG + extra_float_digits;
+
+ if (ndig < 1)
+ ndig = 1;
+
+ sprintf(str, "%.*g", ndig, x);
return TRUE;
} /* single_encode() */
@@ -190,7 +194,12 @@ pair_decode(char *str, float8 *x, float8 *y, char **s)
static int
pair_encode(float8 x, float8 y, char *str)
{
- sprintf(str, "%.*g,%.*g", digits8, x, digits8, y);
+ int ndig = DBL_DIG + extra_float_digits;
+
+ if (ndig < 1)
+ ndig = 1;
+
+ sprintf(str, "%.*g,%.*g", ndig, x, ndig, y);
return TRUE;
}
@@ -976,7 +985,7 @@ line_construct_pts(LINE *line, Point *pt1, Point *pt2)
#endif
#ifdef GEODEBUG
printf("line_construct_pts- line is neither vertical nor horizontal (diffs x=%.*g, y=%.*g\n",
- digits8, (pt2->x - pt1->x), digits8, (pt2->y - pt1->y));
+ DBL_DIG, (pt2->x - pt1->x), DBL_DIG, (pt2->y - pt1->y));
#endif
}
}
@@ -1181,8 +1190,8 @@ line_interpt_internal(LINE *l1, LINE *l2)
#ifdef GEODEBUG
printf("line_interpt- lines are A=%.*g, B=%.*g, C=%.*g, A=%.*g, B=%.*g, C=%.*g\n",
- digits8, l1->A, digits8, l1->B, digits8, l1->C, digits8, l2->A, digits8, l2->B, digits8, l2->C);
- printf("line_interpt- lines intersect at (%.*g,%.*g)\n", digits8, x, digits8, y);
+ DBL_DIG, l1->A, DBL_DIG, l1->B, DBL_DIG, l1->C, DBL_DIG, l2->A, DBL_DIG, l2->B, DBL_DIG, l2->C);
+ printf("line_interpt- lines intersect at (%.*g,%.*g)\n", DBL_DIG, x, DBL_DIG, y);
#endif
return result;
@@ -2381,14 +2390,14 @@ interpt_sl(LSEG *lseg, LINE *line)
p = line_interpt_internal(&tmp, line);
#ifdef GEODEBUG
printf("interpt_sl- segment is (%.*g %.*g) (%.*g %.*g)\n",
- digits8, lseg->p[0].x, digits8, lseg->p[0].y, digits8, lseg->p[1].x, digits8, lseg->p[1].y);
+ DBL_DIG, lseg->p[0].x, DBL_DIG, lseg->p[0].y, DBL_DIG, lseg->p[1].x, DBL_DIG, lseg->p[1].y);
printf("interpt_sl- segment becomes line A=%.*g B=%.*g C=%.*g\n",
- digits8, tmp.A, digits8, tmp.B, digits8, tmp.C);
+ DBL_DIG, tmp.A, DBL_DIG, tmp.B, DBL_DIG, tmp.C);
#endif
if (PointerIsValid(p))
{
#ifdef GEODEBUG
- printf("interpt_sl- intersection point is (%.*g %.*g)\n", digits8, p->x, digits8, p->y);
+ printf("interpt_sl- intersection point is (%.*g %.*g)\n", DBL_DIG, p->x, DBL_DIG, p->y);
#endif
if (on_ps_internal(p, lseg))
{
@@ -3940,7 +3949,7 @@ circle_out(PG_FUNCTION_ARGS)
char *result;
char *cp;
- result = palloc(3 * (P_MAXLEN + 1) + 3);
+ result = palloc(2 * P_MAXLEN + 6);
cp = result;
*cp++ = LDELIM_C;
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 48c3cdb4bf8..ac1c97fedff 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -5,7 +5,7 @@
* command, configuration file, and command line options.
* See src/backend/utils/misc/README for more information.
*
- * $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.99 2002/11/01 22:52:33 tgl Exp $
+ * $Header: /cvsroot/pgsql/src/backend/utils/misc/guc.c,v 1.100 2002/11/08 17:37:52 tgl Exp $
*
* Copyright 2000 by PostgreSQL Global Development Group
* Written by Peter Eisentraut <peter_e@gmx.net>.
@@ -680,6 +680,11 @@ static struct config_int
5, 1, 1000, NULL, NULL
},
+ {
+ {"extra_float_digits", PGC_USERSET}, &extra_float_digits,
+ 0, -15, 2, NULL, NULL
+ },
+
{
{NULL, 0}, NULL, 0, 0, 0, NULL, NULL
}
diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample
index c5973422635..ee721a358a8 100644
--- a/src/backend/utils/misc/postgresql.conf.sample
+++ b/src/backend/utils/misc/postgresql.conf.sample
@@ -127,7 +127,7 @@
#log_duration = false
#log_timestamp = false
-#log_min_error_statement = error # Values in order of increasing severity:
+#log_min_error_statement = error # Values in order of increasing severity:
# debug5, debug4, debug3, debug2, debug1,
# info, notice, warning, error
#debug_print_parse = false
@@ -198,6 +198,7 @@
#authentication_timeout = 60 # 1-600, in seconds
#deadlock_timeout = 1000 # in milliseconds
#default_transaction_isolation = 'read committed'
+#extra_float_digits = 0 # min -15, max 2
#max_expr_depth = 10000 # min 10
#max_files_per_process = 1000 # min 25
#password_encryption = true
diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c
index 0b9a1e8b7a2..2b111bdce5b 100644
--- a/src/bin/pg_dump/pg_dump.c
+++ b/src/bin/pg_dump/pg_dump.c
@@ -22,7 +22,7 @@
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/bin/pg_dump/pg_dump.c,v 1.305 2002/10/22 19:15:23 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/bin/pg_dump/pg_dump.c,v 1.306 2002/11/08 17:37:52 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -171,6 +171,7 @@ main(int argc, char **argv)
const char *pgport = NULL;
const char *username = NULL;
bool oids = false;
+ PGresult *res;
TableInfo *tblinfo;
int numTables;
bool force_password = false;
@@ -549,22 +550,32 @@ main(int argc, char **argv)
/*
* Start serializable transaction to dump consistent data.
*/
- {
- PGresult *res;
+ res = PQexec(g_conn, "BEGIN");
+ if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
+ exit_horribly(g_fout, NULL, "BEGIN command failed: %s",
+ PQerrorMessage(g_conn));
+ PQclear(res);
- res = PQexec(g_conn, "BEGIN");
- if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
- exit_horribly(g_fout, NULL, "BEGIN command failed: %s",
- PQerrorMessage(g_conn));
- PQclear(res);
+ res = PQexec(g_conn, "SET TRANSACTION ISOLATION LEVEL SERIALIZABLE");
+ if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
+ exit_horribly(g_fout, NULL, "could not set transaction isolation level to serializable: %s",
+ PQerrorMessage(g_conn));
+ PQclear(res);
- res = PQexec(g_conn, "SET TRANSACTION ISOLATION LEVEL SERIALIZABLE");
+ /*
+ * If supported, set extra_float_digits so that we can dump float data
+ * exactly (given correctly implemented float I/O code, anyway)
+ */
+ if (g_fout->remoteVersion >= 70400)
+ {
+ res = PQexec(g_conn, "SET extra_float_digits TO 2");
if (!res || PQresultStatus(res) != PGRES_COMMAND_OK)
- exit_horribly(g_fout, NULL, "could not set transaction isolation level to serializable: %s",
+ exit_horribly(g_fout, NULL, "could not set extra_float_digits: %s",
PQerrorMessage(g_conn));
PQclear(res);
}
+ /* Find the last built-in OID, if needed */
if (g_fout->remoteVersion < 70300)
{
if (g_fout->remoteVersion >= 70100)
diff --git a/src/bin/psql/tab-complete.c b/src/bin/psql/tab-complete.c
index ce4a2b5a809..4b3e4c13a9b 100644
--- a/src/bin/psql/tab-complete.c
+++ b/src/bin/psql/tab-complete.c
@@ -3,7 +3,7 @@
*
* Copyright 2000-2002 by PostgreSQL Global Development Group
*
- * $Header: /cvsroot/pgsql/src/bin/psql/tab-complete.c,v 1.64 2002/09/04 20:31:36 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/bin/psql/tab-complete.c,v 1.65 2002/11/08 17:37:52 tgl Exp $
*/
/*----------------------------------------------------------------------
@@ -261,6 +261,7 @@ psql_completion(char *text, int start, int end)
"max_expr_depth",
"commit_delay",
"commit_siblings",
+ "extra_float_digits",
"effective_cache_size",
"random_page_cost",
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
index a933520daa2..f134bdb4955 100644
--- a/src/include/utils/builtins.h
+++ b/src/include/utils/builtins.h
@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $Id: builtins.h,v 1.204 2002/11/02 18:41:22 tgl Exp $
+ * $Id: builtins.h,v 1.205 2002/11/08 17:37:52 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -212,6 +212,8 @@ extern Datum btnamecmp(PG_FUNCTION_ARGS);
extern Datum bttextcmp(PG_FUNCTION_ARGS);
/* float.c */
+extern int extra_float_digits;
+
extern Datum float4in(PG_FUNCTION_ARGS);
extern Datum float4out(PG_FUNCTION_ARGS);
extern Datum float8in(PG_FUNCTION_ARGS);
--
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