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Re: Unexpected interval comparison

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I wrote:
> Looking at what we've got here, it's already a substantial fraction of
> what would be needed to provide a compiler-independent implementation
> of the int128-based aggregate logic in numeric.c.  With that in mind,
> I propose that we extract the relevant stuff into a new header file
> that is designed as general-purpose int128 support.  Something like the
> attached.  I also attach the test program I put together to verify it.

Here's a fleshed-out patch for the original problem based on that.
I found that direct int64-to-int128 coercions were also needed to
handle some of the steps in timestamp.c, so I added those to int128.h.

I think it would be reasonable to back-patch this, although it would
need some adjustments for the back branches since we only recently
got rid of the float-timestamp option.  Also I'd not be inclined to
depend on native int128 any further back than it was already in use.

			regards, tom lane

diff --git a/src/backend/utils/adt/int128.c b/src/backend/utils/adt/int128.c
index ...8bc0663 .
*** a/src/backend/utils/adt/int128.c
--- b/src/backend/utils/adt/int128.c
***************
*** 0 ****
--- 1,181 ----
+ /*-------------------------------------------------------------------------
+  *
+  * int128.c
+  *	  Testbed for roll-our-own 128-bit integer arithmetic.
+  *
+  * This file is not meant to be compiled into the backend; rather, it builds
+  * a standalone test program that compares the behavior of an implementation
+  * in int128.h to an (assumed correct) int128 native type.
+  *
+  * Copyright (c) 2017, PostgreSQL Global Development Group
+  *
+  *
+  * IDENTIFICATION
+  *	  src/backend/utils/adt/int128.c
+  *
+  *-------------------------------------------------------------------------
+  */
+ 
+ #include "postgres.h"
+ 
+ /*
+  * By default, we test the non-native implementation in int128.h; but
+  * by predefining USE_NATIVE_INT128 to 1, you can test the native
+  * implementation, just to be sure.
+  */
+ #ifndef USE_NATIVE_INT128
+ #define USE_NATIVE_INT128 0
+ #endif
+ 
+ #include "utils/int128.h"
+ 
+ /*
+  * We assume the parts of this union are laid out compatibly.
+  */
+ typedef union
+ {
+ 	int128		i128;
+ 	INT128		I128;
+ 	union
+ 	{
+ #ifdef WORDS_BIGENDIAN
+ 		int64		hi;
+ 		uint64		lo;
+ #else
+ 		uint64		lo;
+ 		int64		hi;
+ #endif
+ 	}			hl;
+ } test128;
+ 
+ 
+ /*
+  * Control version of comparator.
+  */
+ static inline int
+ my_int128_compare(int128 x, int128 y)
+ {
+ 	if (x < y)
+ 		return -1;
+ 	if (x > y)
+ 		return 1;
+ 	return 0;
+ }
+ 
+ /*
+  * Get a random uint64 value.
+  * We don't assume random() is good for more than 16 bits.
+  */
+ static uint64
+ get_random_uint64(void)
+ {
+ 	uint64		x;
+ 
+ 	x = (uint64) (random() & 0xFFFF) << 48;
+ 	x |= (uint64) (random() & 0xFFFF) << 32;
+ 	x |= (uint64) (random() & 0xFFFF) << 16;
+ 	x |= (uint64) (random() & 0xFFFF);
+ 	return x;
+ }
+ 
+ /*
+  * Main program.
+  *
+  * You can give it a loop count if you don't like the default 1B iterations.
+  */
+ int
+ main(int argc, char **argv)
+ {
+ 	long		count;
+ 
+ 	if (argc >= 2)
+ 		count = strtol(argv[1], NULL, 0);
+ 	else
+ 		count = 1000000000;
+ 
+ 	while (count-- > 0)
+ 	{
+ 		int64		x = get_random_uint64();
+ 		int64		y = get_random_uint64();
+ 		int64		z = get_random_uint64();
+ 		test128		t1;
+ 		test128		t2;
+ 
+ 		/* check unsigned addition */
+ 		t1.hl.hi = x;
+ 		t1.hl.lo = y;
+ 		t2 = t1;
+ 		t1.i128 += (int128) (uint64) z;
+ 		int128_add_uint64(&t2.I128, (uint64) z);
+ 
+ 		if (t1.hl.hi != t2.hl.hi || t1.hl.lo != t2.hl.lo)
+ 		{
+ 			printf("%016lX%016lX + unsigned %lX\n", x, y, z);
+ 			printf("native = %016lX%016lX\n", t1.hl.hi, t1.hl.lo);
+ 			printf("result = %016lX%016lX\n", t2.hl.hi, t2.hl.lo);
+ 			return 1;
+ 		}
+ 
+ 		/* check signed addition */
+ 		t1.hl.hi = x;
+ 		t1.hl.lo = y;
+ 		t2 = t1;
+ 		t1.i128 += (int128) z;
+ 		int128_add_int64(&t2.I128, z);
+ 
+ 		if (t1.hl.hi != t2.hl.hi || t1.hl.lo != t2.hl.lo)
+ 		{
+ 			printf("%016lX%016lX + signed %lX\n", x, y, z);
+ 			printf("native = %016lX%016lX\n", t1.hl.hi, t1.hl.lo);
+ 			printf("result = %016lX%016lX\n", t2.hl.hi, t2.hl.lo);
+ 			return 1;
+ 		}
+ 
+ 		/* check multiplication */
+ 		t1.i128 = (int128) x *(int128) y;
+ 
+ 		t2.hl.hi = t2.hl.lo = 0;
+ 		int128_add_int64_mul_int64(&t2.I128, x, y);
+ 
+ 		if (t1.hl.hi != t2.hl.hi || t1.hl.lo != t2.hl.lo)
+ 		{
+ 			printf("%lX * %lX\n", x, y);
+ 			printf("native = %016lX%016lX\n", t1.hl.hi, t1.hl.lo);
+ 			printf("result = %016lX%016lX\n", t2.hl.hi, t2.hl.lo);
+ 			return 1;
+ 		}
+ 
+ 		/* check comparison */
+ 		t1.hl.hi = x;
+ 		t1.hl.lo = y;
+ 		t2.hl.hi = z;
+ 		t2.hl.lo = get_random_uint64();
+ 
+ 		if (my_int128_compare(t1.i128, t2.i128) !=
+ 			int128_compare(t1.I128, t2.I128))
+ 		{
+ 			printf("comparison failure: %d vs %d\n",
+ 				   my_int128_compare(t1.i128, t2.i128),
+ 				   int128_compare(t1.I128, t2.I128));
+ 			printf("arg1 = %016lX%016lX\n", t1.hl.hi, t1.hl.lo);
+ 			printf("arg2 = %016lX%016lX\n", t2.hl.hi, t2.hl.lo);
+ 			return 1;
+ 		}
+ 
+ 		/* check case with identical hi parts; above will hardly ever hit it */
+ 		t2.hl.hi = x;
+ 
+ 		if (my_int128_compare(t1.i128, t2.i128) !=
+ 			int128_compare(t1.I128, t2.I128))
+ 		{
+ 			printf("comparison failure: %d vs %d\n",
+ 				   my_int128_compare(t1.i128, t2.i128),
+ 				   int128_compare(t1.I128, t2.I128));
+ 			printf("arg1 = %016lX%016lX\n", t1.hl.hi, t1.hl.lo);
+ 			printf("arg2 = %016lX%016lX\n", t2.hl.hi, t2.hl.lo);
+ 			return 1;
+ 		}
+ 	}
+ 
+ 	return 0;
+ }
diff --git a/src/backend/utils/adt/timestamp.c b/src/backend/utils/adt/timestamp.c
index 4be1999..88ecb78 100644
*** a/src/backend/utils/adt/timestamp.c
--- b/src/backend/utils/adt/timestamp.c
***************
*** 33,38 ****
--- 33,40 ----
  #include "utils/array.h"
  #include "utils/builtins.h"
  #include "utils/datetime.h"
+ #include "utils/int128.h"
+ 
  
  /*
   * gcc's -ffast-math switch breaks routines that expect exact results from
*************** timestamptz_cmp_timestamp(PG_FUNCTION_AR
*** 2288,2302 ****
  
  /*
   *		interval_relop	- is interval1 relop interval2
   */
! static inline TimeOffset
  interval_cmp_value(const Interval *interval)
  {
! 	TimeOffset	span;
  
! 	span = interval->time;
! 	span += interval->month * INT64CONST(30) * USECS_PER_DAY;
! 	span += interval->day * INT64CONST(24) * USECS_PER_HOUR;
  
  	return span;
  }
--- 2290,2324 ----
  
  /*
   *		interval_relop	- is interval1 relop interval2
+  *
+  * Interval comparison is based on converting interval values to a linear
+  * representation expressed in the units of the time field (microseconds,
+  * in the case of integer timestamps) with days assumed to be always 24 hours
+  * and months assumed to be always 30 days.  To avoid overflow, we need a
+  * wider-than-int64 datatype for the linear representation, so use INT128.
   */
! 
! static inline INT128
  interval_cmp_value(const Interval *interval)
  {
! 	INT128		span;
! 	int64		dayfraction;
! 	int64		days;
  
! 	/*
! 	 * Separate time field into days and dayfraction, then add the month and
! 	 * day fields to the days part.  We cannot overflow int64 days here.
! 	 */
! 	dayfraction = interval->time % USECS_PER_DAY;
! 	days = interval->time / USECS_PER_DAY;
! 	days += interval->month * INT64CONST(30);
! 	days += interval->day;
! 
! 	/* Widen dayfraction to 128 bits */
! 	span = int64_to_int128(dayfraction);
! 
! 	/* Scale up days to microseconds, forming a 128-bit product */
! 	int128_add_int64_mul_int64(&span, days, USECS_PER_DAY);
  
  	return span;
  }
*************** interval_cmp_value(const Interval *inter
*** 2304,2313 ****
  static int
  interval_cmp_internal(Interval *interval1, Interval *interval2)
  {
! 	TimeOffset	span1 = interval_cmp_value(interval1);
! 	TimeOffset	span2 = interval_cmp_value(interval2);
  
! 	return ((span1 < span2) ? -1 : (span1 > span2) ? 1 : 0);
  }
  
  Datum
--- 2326,2335 ----
  static int
  interval_cmp_internal(Interval *interval1, Interval *interval2)
  {
! 	INT128		span1 = interval_cmp_value(interval1);
! 	INT128		span2 = interval_cmp_value(interval2);
  
! 	return int128_compare(span1, span2);
  }
  
  Datum
*************** Datum
*** 2384,2392 ****
  interval_hash(PG_FUNCTION_ARGS)
  {
  	Interval   *interval = PG_GETARG_INTERVAL_P(0);
! 	TimeOffset	span = interval_cmp_value(interval);
  
! 	return DirectFunctionCall1(hashint8, Int64GetDatumFast(span));
  }
  
  /* overlaps_timestamp() --- implements the SQL OVERLAPS operator.
--- 2406,2423 ----
  interval_hash(PG_FUNCTION_ARGS)
  {
  	Interval   *interval = PG_GETARG_INTERVAL_P(0);
! 	INT128		span = interval_cmp_value(interval);
! 	int64		span64;
  
! 	/*
! 	 * Use only the least significant 64 bits for hashing.  The upper 64 bits
! 	 * seldom add any useful information, and besides we must do it like this
! 	 * for compatibility with hashes calculated before use of INT128 was
! 	 * introduced.
! 	 */
! 	span64 = int128_to_int64(span);
! 
! 	return DirectFunctionCall1(hashint8, Int64GetDatumFast(span64));
  }
  
  /* overlaps_timestamp() --- implements the SQL OVERLAPS operator.
diff --git a/src/include/utils/int128.h b/src/include/utils/int128.h
index ...876610b .
*** a/src/include/utils/int128.h
--- b/src/include/utils/int128.h
***************
*** 0 ****
--- 1,274 ----
+ /*-------------------------------------------------------------------------
+  *
+  * int128.h
+  *	  Roll-our-own 128-bit integer arithmetic.
+  *
+  * We make use of the native int128 type if there is one, otherwise
+  * implement things the hard way based on two int64 halves.
+  *
+  * Copyright (c) 2017, PostgreSQL Global Development Group
+  *
+  * src/include/utils/int128.h
+  *
+  *-------------------------------------------------------------------------
+  */
+ #ifndef INT128_H
+ #define INT128_H
+ 
+ /*
+  * For testing purposes, use of native int128 can be switched on/off by
+  * predefining USE_NATIVE_INT128.
+  */
+ #ifndef USE_NATIVE_INT128
+ #ifdef HAVE_INT128
+ #define USE_NATIVE_INT128 1
+ #else
+ #define USE_NATIVE_INT128 0
+ #endif
+ #endif
+ 
+ 
+ #if USE_NATIVE_INT128
+ 
+ typedef int128 INT128;
+ 
+ /*
+  * Add an unsigned int64 value into an INT128 variable.
+  */
+ static inline void
+ int128_add_uint64(INT128 *i128, uint64 v)
+ {
+ 	*i128 += v;
+ }
+ 
+ /*
+  * Add a signed int64 value into an INT128 variable.
+  */
+ static inline void
+ int128_add_int64(INT128 *i128, int64 v)
+ {
+ 	*i128 += v;
+ }
+ 
+ /*
+  * Add the 128-bit product of two int64 values into an INT128 variable.
+  *
+  * XXX with a stupid compiler, this could actually be less efficient than
+  * the other implementation; maybe we should do it by hand always?
+  */
+ static inline void
+ int128_add_int64_mul_int64(INT128 *i128, int64 x, int64 y)
+ {
+ 	*i128 += (int128) x *(int128) y;
+ }
+ 
+ /*
+  * Compare two INT128 values, return -1, 0, or +1.
+  */
+ static inline int
+ int128_compare(INT128 x, INT128 y)
+ {
+ 	if (x < y)
+ 		return -1;
+ 	if (x > y)
+ 		return 1;
+ 	return 0;
+ }
+ 
+ /*
+  * Widen int64 to INT128.
+  */
+ static inline INT128
+ int64_to_int128(int64 v)
+ {
+ 	return (INT128) v;
+ }
+ 
+ /*
+  * Convert INT128 to int64 (losing any high-order bits).
+  * This also works fine for casting down to uint64.
+  */
+ static inline int64
+ int128_to_int64(INT128 val)
+ {
+ 	return (int64) val;
+ }
+ 
+ #else							/* !USE_NATIVE_INT128 */
+ 
+ /*
+  * We lay out the INT128 structure with the same content and byte ordering
+  * that a native int128 type would (probably) have.  This makes no difference
+  * for ordinary use of INT128, but allows union'ing INT128 with int128 for
+  * testing purposes.
+  */
+ typedef struct
+ {
+ #ifdef WORDS_BIGENDIAN
+ 	int64		hi;				/* most significant 64 bits, including sign */
+ 	uint64		lo;				/* least significant 64 bits, without sign */
+ #else
+ 	uint64		lo;				/* least significant 64 bits, without sign */
+ 	int64		hi;				/* most significant 64 bits, including sign */
+ #endif
+ } INT128;
+ 
+ /*
+  * Add an unsigned int64 value into an INT128 variable.
+  */
+ static inline void
+ int128_add_uint64(INT128 *i128, uint64 v)
+ {
+ 	/*
+ 	 * First add the value to the .lo part, then check to see if a carry needs
+ 	 * to be propagated into the .hi part.  A carry is needed if both inputs
+ 	 * have high bits set, or if just one input has high bit set while the new
+ 	 * .lo part doesn't.  Remember that .lo part is unsigned; we cast to
+ 	 * signed here just as a cheap way to check the high bit.
+ 	 */
+ 	uint64		oldlo = i128->lo;
+ 
+ 	i128->lo += v;
+ 	if (((int64) v < 0 && (int64) oldlo < 0) ||
+ 		(((int64) v < 0 || (int64) oldlo < 0) && (int64) i128->lo >= 0))
+ 		i128->hi++;
+ }
+ 
+ /*
+  * Add a signed int64 value into an INT128 variable.
+  */
+ static inline void
+ int128_add_int64(INT128 *i128, int64 v)
+ {
+ 	/*
+ 	 * This is much like the above except that the carry logic differs for
+ 	 * negative v.  Ordinarily we'd need to subtract 1 from the .hi part
+ 	 * (corresponding to adding the sign-extended bits of v to it); but if
+ 	 * there is a carry out of the .lo part, that cancels and we do nothing.
+ 	 */
+ 	uint64		oldlo = i128->lo;
+ 
+ 	i128->lo += v;
+ 	if (v >= 0)
+ 	{
+ 		if ((int64) oldlo < 0 && (int64) i128->lo >= 0)
+ 			i128->hi++;
+ 	}
+ 	else
+ 	{
+ 		if (!((int64) oldlo < 0 || (int64) i128->lo >= 0))
+ 			i128->hi--;
+ 	}
+ }
+ 
+ /*
+  * INT64_AU32 extracts the most significant 32 bits of int64 as int64, while
+  * INT64_AL32 extracts the least significant 32 bits as uint64.
+  */
+ #define INT64_AU32(i64) ((i64) >> 32)
+ #define INT64_AL32(i64) ((i64) & UINT64CONST(0xFFFFFFFF))
+ 
+ /*
+  * Add the 128-bit product of two int64 values into an INT128 variable.
+  */
+ static inline void
+ int128_add_int64_mul_int64(INT128 *i128, int64 x, int64 y)
+ {
+ 	/* INT64_AU32 must use arithmetic right shift */
+ 	StaticAssertStmt(((int64) -1 >> 1) == (int64) -1,
+ 					 "arithmetic right shift is needed");
+ 
+ 	/*----------
+ 	 * Form the 128-bit product x * y using 64-bit arithmetic.
+ 	 * Considering each 64-bit input as having 32-bit high and low parts,
+ 	 * we can compute
+ 	 *
+ 	 *	 x * y = ((x.hi << 32) + x.lo) * (((y.hi << 32) + y.lo)
+ 	 *		   = (x.hi * y.hi) << 64 +
+ 	 *			 (x.hi * y.lo) << 32 +
+ 	 *			 (x.lo * y.hi) << 32 +
+ 	 *			 x.lo * y.lo
+ 	 *
+ 	 * Each individual product is of 32-bit terms so it won't overflow when
+ 	 * computed in 64-bit arithmetic.  Then we just have to shift it to the
+ 	 * correct position while adding into the 128-bit result.  We must also
+ 	 * keep in mind that the "lo" parts must be treated as unsigned.
+ 	 *----------
+ 	 */
+ 
+ 	/* No need to work hard if product must be zero */
+ 	if (x != 0 && y != 0)
+ 	{
+ 		int64		x_u32 = INT64_AU32(x);
+ 		uint64		x_l32 = INT64_AL32(x);
+ 		int64		y_u32 = INT64_AU32(y);
+ 		uint64		y_l32 = INT64_AL32(y);
+ 		int64		tmp;
+ 
+ 		/* the first term */
+ 		i128->hi += x_u32 * y_u32;
+ 
+ 		/* the second term: sign-extend it only if x is negative */
+ 		tmp = x_u32 * y_l32;
+ 		if (x < 0)
+ 			i128->hi += INT64_AU32(tmp);
+ 		else
+ 			i128->hi += ((uint64) tmp) >> 32;
+ 		int128_add_uint64(i128, ((uint64) INT64_AL32(tmp)) << 32);
+ 
+ 		/* the third term: sign-extend it only if y is negative */
+ 		tmp = x_l32 * y_u32;
+ 		if (y < 0)
+ 			i128->hi += INT64_AU32(tmp);
+ 		else
+ 			i128->hi += ((uint64) tmp) >> 32;
+ 		int128_add_uint64(i128, ((uint64) INT64_AL32(tmp)) << 32);
+ 
+ 		/* the fourth term: always unsigned */
+ 		int128_add_uint64(i128, x_l32 * y_l32);
+ 	}
+ }
+ 
+ /*
+  * Compare two INT128 values, return -1, 0, or +1.
+  */
+ static inline int
+ int128_compare(INT128 x, INT128 y)
+ {
+ 	if (x.hi < y.hi)
+ 		return -1;
+ 	if (x.hi > y.hi)
+ 		return 1;
+ 	if (x.lo < y.lo)
+ 		return -1;
+ 	if (x.lo > y.lo)
+ 		return 1;
+ 	return 0;
+ }
+ 
+ /*
+  * Widen int64 to INT128.
+  */
+ static inline INT128
+ int64_to_int128(int64 v)
+ {
+ 	INT128		val;
+ 
+ 	val.lo = (uint64) v;
+ 	val.hi = (v < 0) ? -INT64CONST(1) : INT64CONST(0);
+ 	return val;
+ }
+ 
+ /*
+  * Convert INT128 to int64 (losing any high-order bits).
+  * This also works fine for casting down to uint64.
+  */
+ static inline int64
+ int128_to_int64(INT128 val)
+ {
+ 	return (int64) val.lo;
+ }
+ 
+ #endif   /* USE_NATIVE_INT128 */
+ 
+ #endif   /* INT128_H */
diff --git a/src/test/regress/expected/interval.out b/src/test/regress/expected/interval.out
index 946c97a..d4e6a00 100644
*** a/src/test/regress/expected/interval.out
--- b/src/test/regress/expected/interval.out
*************** SELECT '' AS fortyfive, r1.*, r2.*
*** 207,212 ****
--- 207,248 ----
             | 34 years        | 6 years
  (45 rows)
  
+ -- intervals out of 64bit linear value in microseconds
+ CREATE TABLE INTERVAL_TBL_OF (f1 interval);
+ INSERT INTO INTERVAL_TBL_OF (f1) VALUES ('2147483647 days 2147483647 months');
+ INSERT INTO INTERVAL_TBL_OF (f1) VALUES ('1 year');
+ INSERT INTO INTERVAL_TBL_OF (f1) VALUES ('-2147483648 days -2147483648 months');
+ SELECT '' AS "64bits", r1.*, r2.*
+    FROM INTERVAL_TBL_OF r1, INTERVAL_TBL_OF r2
+    WHERE r1.f1 > r2.f1
+    ORDER BY r1.f1, r2.f1;
+  64bits |                   f1                   |                    f1                     
+ --------+----------------------------------------+-------------------------------------------
+         | 1 year                                 | -178956970 years -8 mons -2147483648 days
+         | 178956970 years 7 mons 2147483647 days | -178956970 years -8 mons -2147483648 days
+         | 178956970 years 7 mons 2147483647 days | 1 year
+ (3 rows)
+ 
+ CREATE INDEX ON INTERVAL_TBL_OF USING btree (f1);
+ SET enable_seqscan to false;
+ EXPLAIN SELECT '' AS "64bits_2", f1
+   FROM INTERVAL_TBL_OF r1 ORDER BY f1;
+                                                QUERY PLAN                                               
+ --------------------------------------------------------------------------------------------------------
+  Index Only Scan using interval_tbl_of_f1_idx on interval_tbl_of r1  (cost=0.13..12.18 rows=3 width=48)
+ (1 row)
+ 
+ SELECT '' AS "64bits_2", f1
+   FROM INTERVAL_TBL_OF r1 ORDER BY f1;
+  64bits_2 |                    f1                     
+ ----------+-------------------------------------------
+           | -178956970 years -8 mons -2147483648 days
+           | 1 year
+           | 178956970 years 7 mons 2147483647 days
+ (3 rows)
+ 
+ SET enable_seqscan to default;
+ DROP TABLE INTERVAL_TBL_OF;
  -- Test multiplication and division with intervals.
  -- Floating point arithmetic rounding errors can lead to unexpected results,
  -- though the code attempts to do the right thing and round up to days and
diff --git a/src/test/regress/sql/interval.sql b/src/test/regress/sql/interval.sql
index cff9ada..aa21673 100644
*** a/src/test/regress/sql/interval.sql
--- b/src/test/regress/sql/interval.sql
*************** SELECT '' AS fortyfive, r1.*, r2.*
*** 59,64 ****
--- 59,81 ----
     WHERE r1.f1 > r2.f1
     ORDER BY r1.f1, r2.f1;
  
+ -- intervals out of 64bit linear value in microseconds
+ CREATE TABLE INTERVAL_TBL_OF (f1 interval);
+ INSERT INTO INTERVAL_TBL_OF (f1) VALUES ('2147483647 days 2147483647 months');
+ INSERT INTO INTERVAL_TBL_OF (f1) VALUES ('1 year');
+ INSERT INTO INTERVAL_TBL_OF (f1) VALUES ('-2147483648 days -2147483648 months');
+ SELECT '' AS "64bits", r1.*, r2.*
+    FROM INTERVAL_TBL_OF r1, INTERVAL_TBL_OF r2
+    WHERE r1.f1 > r2.f1
+    ORDER BY r1.f1, r2.f1;
+ CREATE INDEX ON INTERVAL_TBL_OF USING btree (f1);
+ SET enable_seqscan to false;
+ EXPLAIN SELECT '' AS "64bits_2", f1
+   FROM INTERVAL_TBL_OF r1 ORDER BY f1;
+ SELECT '' AS "64bits_2", f1
+   FROM INTERVAL_TBL_OF r1 ORDER BY f1;
+ SET enable_seqscan to default;
+ DROP TABLE INTERVAL_TBL_OF;
  
  -- Test multiplication and division with intervals.
  -- Floating point arithmetic rounding errors can lead to unexpected results,
-- 
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