Teach pg_size_pretty and pg_size_bytes about petabytes

There was talk about adding units all the way up to yottabytes but it
seems quite far-fetched that anyone would need those.  Since such large
units are not exactly commonplace, it seems unlikely that having
pg_size_pretty outputting unit any larger than petabytes would actually be
helpful to anyone.

Since petabytes are on the horizon, let's just add those only.  Maybe one
day we'll get to add additional units, but it will likely be a while
before we'll need to think beyond petabytes in regards to the size of a
database.

Author: David Christensen
Discussion: https://postgr.es/m/CAOxo6XKmHc_WZip-x5QwaOqFEiCq_SVD0B7sbTZQk+qqcn2qaw@mail.gmail.com

3 files changed, 72 insertions, 64 deletions

diff --git a/src/backend/utils/adt/dbsize.c b/src/backend/utils/adt/dbsize.c
index 6c381b02b7e..d5a7fb13f3c 100644
--- a/src/backend/utils/adt/dbsize.c
+++ b/src/backend/utils/adt/dbsize.c
@@ -52,6 +52,7 @@ static const struct size_pretty_unit size_pretty_units[] = {
 	{"MB", 20 * 1024 - 1, true, 20},
 	{"GB", 20 * 1024 - 1, true, 30},
 	{"TB", 20 * 1024 - 1, true, 40},
+	{"PB", 20 * 1024 - 1, true, 50},
 	{NULL, 0, false, 0}
 };
 
@@ -811,7 +812,7 @@ pg_size_bytes(PG_FUNCTION_ARGS)
 					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 					 errmsg("invalid size: \"%s\"", text_to_cstring(arg)),
 					 errdetail("Invalid size unit: \"%s\".", strptr),
-					 errhint("Valid units are \"bytes\", \"kB\", \"MB\", \"GB\", and \"TB\".")));
+					 errhint("Valid units are \"bytes\", \"kB\", \"MB\", \"GB\", \"TB\", and \"PB\".")));
 
 		if (multiplier > 1)
 		{
diff --git a/src/test/regress/expected/dbsize.out b/src/test/regress/expected/dbsize.out
index 29804aee8b8..d8d6686b5f4 100644
--- a/src/test/regress/expected/dbsize.out
+++ b/src/test/regress/expected/dbsize.out
@@ -53,7 +53,7 @@ SELECT size, pg_size_pretty(size), pg_size_pretty(-1 * size) FROM
     10994579406847 | 10239 GB       | -10239 GB
     10994579406848 | 10 TB          | -10 TB
  11258449312612351 | 10239 TB       | -10239 TB
- 11258449312612352 | 10240 TB       | -10240 TB
+ 11258449312612352 | 10 PB          | -10 PB
 (10 rows)
 
 SELECT size, pg_size_pretty(size), pg_size_pretty(-1 * size) FROM
@@ -61,71 +61,77 @@ SELECT size, pg_size_pretty(size), pg_size_pretty(-1 * size) FROM
             (10485247::numeric), (10485248::numeric),
             (10736893951::numeric), (10736893952::numeric),
             (10994579406847::numeric), (10994579406848::numeric),
-            (11258449312612351::numeric), (11258449312612352::numeric)) x(size);
-       size        | pg_size_pretty | pg_size_pretty 
--------------------+----------------+----------------
-             10239 | 10239 bytes    | -10239 bytes
-             10240 | 10 kB          | -10 kB
-          10485247 | 10239 kB       | -10239 kB
-          10485248 | 10 MB          | -10 MB
-       10736893951 | 10239 MB       | -10239 MB
-       10736893952 | 10 GB          | -10 GB
-    10994579406847 | 10239 GB       | -10239 GB
-    10994579406848 | 10 TB          | -10 TB
- 11258449312612351 | 10239 TB       | -10239 TB
- 11258449312612352 | 10240 TB       | -10240 TB
-(10 rows)
+            (11258449312612351::numeric), (11258449312612352::numeric),
+            (11528652096115048447::numeric), (11528652096115048448::numeric)) x(size);
+         size         | pg_size_pretty | pg_size_pretty 
+----------------------+----------------+----------------
+                10239 | 10239 bytes    | -10239 bytes
+                10240 | 10 kB          | -10 kB
+             10485247 | 10239 kB       | -10239 kB
+             10485248 | 10 MB          | -10 MB
+          10736893951 | 10239 MB       | -10239 MB
+          10736893952 | 10 GB          | -10 GB
+       10994579406847 | 10239 GB       | -10239 GB
+       10994579406848 | 10 TB          | -10 TB
+    11258449312612351 | 10239 TB       | -10239 TB
+    11258449312612352 | 10 PB          | -10 PB
+ 11528652096115048447 | 10239 PB       | -10239 PB
+ 11528652096115048448 | 10240 PB       | -10240 PB
+(12 rows)
 
 -- pg_size_bytes() tests
 SELECT size, pg_size_bytes(size) FROM
     (VALUES ('1'), ('123bytes'), ('1kB'), ('1MB'), (' 1 GB'), ('1.5 GB '),
-            ('1TB'), ('3000 TB'), ('1e6 MB')) x(size);
-   size   |  pg_size_bytes   
-----------+------------------
- 1        |                1
- 123bytes |              123
- 1kB      |             1024
- 1MB      |          1048576
-  1 GB    |       1073741824
- 1.5 GB   |       1610612736
- 1TB      |    1099511627776
- 3000 TB  | 3298534883328000
- 1e6 MB   |    1048576000000
-(9 rows)
+            ('1TB'), ('3000 TB'), ('1e6 MB'), ('99 PB')) x(size);
+   size   |   pg_size_bytes    
+----------+--------------------
+ 1        |                  1
+ 123bytes |                123
+ 1kB      |               1024
+ 1MB      |            1048576
+  1 GB    |         1073741824
+ 1.5 GB   |         1610612736
+ 1TB      |      1099511627776
+ 3000 TB  |   3298534883328000
+ 1e6 MB   |      1048576000000
+ 99 PB    | 111464090777419776
+(10 rows)
 
 -- case-insensitive units are supported
 SELECT size, pg_size_bytes(size) FROM
     (VALUES ('1'), ('123bYteS'), ('1kb'), ('1mb'), (' 1 Gb'), ('1.5 gB '),
-            ('1tb'), ('3000 tb'), ('1e6 mb')) x(size);
-   size   |  pg_size_bytes   
-----------+------------------
- 1        |                1
- 123bYteS |              123
- 1kb      |             1024
- 1mb      |          1048576
-  1 Gb    |       1073741824
- 1.5 gB   |       1610612736
- 1tb      |    1099511627776
- 3000 tb  | 3298534883328000
- 1e6 mb   |    1048576000000
-(9 rows)
+            ('1tb'), ('3000 tb'), ('1e6 mb'), ('99 pb')) x(size);
+   size   |   pg_size_bytes    
+----------+--------------------
+ 1        |                  1
+ 123bYteS |                123
+ 1kb      |               1024
+ 1mb      |            1048576
+  1 Gb    |         1073741824
+ 1.5 gB   |         1610612736
+ 1tb      |      1099511627776
+ 3000 tb  |   3298534883328000
+ 1e6 mb   |      1048576000000
+ 99 pb    | 111464090777419776
+(10 rows)
 
 -- negative numbers are supported
 SELECT size, pg_size_bytes(size) FROM
     (VALUES ('-1'), ('-123bytes'), ('-1kb'), ('-1mb'), (' -1 Gb'), ('-1.5 gB '),
-            ('-1tb'), ('-3000 TB'), ('-10e-1 MB')) x(size);
-   size    |   pg_size_bytes   
------------+-------------------
- -1        |                -1
- -123bytes |              -123
- -1kb      |             -1024
- -1mb      |          -1048576
-  -1 Gb    |       -1073741824
- -1.5 gB   |       -1610612736
- -1tb      |    -1099511627776
- -3000 TB  | -3298534883328000
- -10e-1 MB |          -1048576
-(9 rows)
+            ('-1tb'), ('-3000 TB'), ('-10e-1 MB'), ('-99 PB')) x(size);
+   size    |    pg_size_bytes    
+-----------+---------------------
+ -1        |                  -1
+ -123bytes |                -123
+ -1kb      |               -1024
+ -1mb      |            -1048576
+  -1 Gb    |         -1073741824
+ -1.5 gB   |         -1610612736
+ -1tb      |      -1099511627776
+ -3000 TB  |   -3298534883328000
+ -10e-1 MB |            -1048576
+ -99 PB    | -111464090777419776
+(10 rows)
 
 -- different cases with allowed points
 SELECT size, pg_size_bytes(size) FROM
@@ -147,15 +153,15 @@ SELECT size, pg_size_bytes(size) FROM
 SELECT pg_size_bytes('1 AB');
 ERROR:  invalid size: "1 AB"
 DETAIL:  Invalid size unit: "AB".
-HINT:  Valid units are "bytes", "kB", "MB", "GB", and "TB".
+HINT:  Valid units are "bytes", "kB", "MB", "GB", "TB", and "PB".
 SELECT pg_size_bytes('1 AB A');
 ERROR:  invalid size: "1 AB A"
 DETAIL:  Invalid size unit: "AB A".
-HINT:  Valid units are "bytes", "kB", "MB", "GB", and "TB".
+HINT:  Valid units are "bytes", "kB", "MB", "GB", "TB", and "PB".
 SELECT pg_size_bytes('1 AB A    ');
 ERROR:  invalid size: "1 AB A    "
 DETAIL:  Invalid size unit: "AB A".
-HINT:  Valid units are "bytes", "kB", "MB", "GB", and "TB".
+HINT:  Valid units are "bytes", "kB", "MB", "GB", "TB", and "PB".
 SELECT pg_size_bytes('9223372036854775807.9');
 ERROR:  bigint out of range
 SELECT pg_size_bytes('1e100');
@@ -165,7 +171,7 @@ ERROR:  value overflows numeric format
 SELECT pg_size_bytes('1 byte');  -- the singular "byte" is not supported
 ERROR:  invalid size: "1 byte"
 DETAIL:  Invalid size unit: "byte".
-HINT:  Valid units are "bytes", "kB", "MB", "GB", and "TB".
+HINT:  Valid units are "bytes", "kB", "MB", "GB", "TB", and "PB".
 SELECT pg_size_bytes('');
 ERROR:  invalid size: ""
 SELECT pg_size_bytes('kb');
@@ -183,6 +189,6 @@ ERROR:  invalid size: ".+912"
 SELECT pg_size_bytes('+912+ kB');
 ERROR:  invalid size: "+912+ kB"
 DETAIL:  Invalid size unit: "+ kB".
-HINT:  Valid units are "bytes", "kB", "MB", "GB", and "TB".
+HINT:  Valid units are "bytes", "kB", "MB", "GB", "TB", and "PB".
 SELECT pg_size_bytes('++123 kB');
 ERROR:  invalid size: "++123 kB"
diff --git a/src/test/regress/sql/dbsize.sql b/src/test/regress/sql/dbsize.sql
index 6a45c5eb1cf..7df865271b6 100644
--- a/src/test/regress/sql/dbsize.sql
+++ b/src/test/regress/sql/dbsize.sql
@@ -24,22 +24,23 @@ SELECT size, pg_size_pretty(size), pg_size_pretty(-1 * size) FROM
             (10485247::numeric), (10485248::numeric),
             (10736893951::numeric), (10736893952::numeric),
             (10994579406847::numeric), (10994579406848::numeric),
-            (11258449312612351::numeric), (11258449312612352::numeric)) x(size);
+            (11258449312612351::numeric), (11258449312612352::numeric),
+            (11528652096115048447::numeric), (11528652096115048448::numeric)) x(size);
 
 -- pg_size_bytes() tests
 SELECT size, pg_size_bytes(size) FROM
     (VALUES ('1'), ('123bytes'), ('1kB'), ('1MB'), (' 1 GB'), ('1.5 GB '),
-            ('1TB'), ('3000 TB'), ('1e6 MB')) x(size);
+            ('1TB'), ('3000 TB'), ('1e6 MB'), ('99 PB')) x(size);
 
 -- case-insensitive units are supported
 SELECT size, pg_size_bytes(size) FROM
     (VALUES ('1'), ('123bYteS'), ('1kb'), ('1mb'), (' 1 Gb'), ('1.5 gB '),
-            ('1tb'), ('3000 tb'), ('1e6 mb')) x(size);
+            ('1tb'), ('3000 tb'), ('1e6 mb'), ('99 pb')) x(size);
 
 -- negative numbers are supported
 SELECT size, pg_size_bytes(size) FROM
     (VALUES ('-1'), ('-123bytes'), ('-1kb'), ('-1mb'), (' -1 Gb'), ('-1.5 gB '),
-            ('-1tb'), ('-3000 TB'), ('-10e-1 MB')) x(size);
+            ('-1tb'), ('-3000 TB'), ('-10e-1 MB'), ('-99 PB')) x(size);
 
 -- different cases with allowed points
 SELECT size, pg_size_bytes(size) FROM