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MDEV-27208: Extend CRC32() and implement CRC32C()

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We used to define a native unary function CRC32() that computes the CRC-32
of a string using the ISO 3309 polynomial that is being used by zlib
and many others.

Often, a CRC is computed in pieces. To faciliate this, we introduce a
2-ary variant of the function that inputs a previous CRC as the first
argument: CRC32('MariaDB')=CRC32(CRC32('Maria'),'DB').

InnoDB and MyRocks use a different polynomial, which was implemented
in SSE4.2 instructions that were introduced in the
Intel Nehalem microarchitecture. This is commonly called CRC-32C
(Castagnoli).

We introduce a native function that uses the Castagnoli polynomial:
CRC32C('MariaDB')=CRC32C(CRC32C('Maria'),'DB'). This allows
SELECT...INTO DUMPFILE to be used for the creation of files with
valid checksums, such as a logically empty InnoDB redo log file
ib_logfile0 corresponding to a particular log sequence number.
This commit is contained in:
Marko Mäkelä
2022-01-21 19:24:00 +02:00
parent b07920b634
commit 5b3ad94c7b
6 changed files with 254 additions and 32 deletions
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117
mysql-test/main/func_math.result
View File

@ -1840,24 +1840,115 @@ CRC32(99999999999999999999999999999999)
SELECT CRC32(-99999999999999999999999999999999);
CRC32(-99999999999999999999999999999999)
1052326872
SELECT CRC32C(NULL), CRC32C(''), CRC32C('MariaDB'), CRC32C('mariadb');
CRC32C(NULL) CRC32C('') CRC32C('MariaDB') CRC32C('mariadb')
NULL 0 809606978 1378644259
SELECT CRC32(NULL,1),CRC32C(NULL,1), CRC32(1,''), CRC32C(1,'');
CRC32(NULL,1) CRC32C(NULL,1) CRC32(1,'') CRC32C(1,'')
NULL NULL 1 1
SELECT CRC32(42,''),CRC32C(42,''),CRC32('42',''),CRC32C('42','');
CRC32(42,'') CRC32C(42,'') CRC32('42','') CRC32C('42','')
42 42 42 42
SELECT CRC32(42,NULL),CRC32C(42,NULL);
CRC32(42,NULL) CRC32C(42,NULL)
NULL NULL
SELECT CRC32 ('5c',''),CRC32 ('5c',0),CRC32 ('5c', '0'),CRC32 ('5c',NULL);
CRC32 ('5c','') CRC32 ('5c',0) CRC32 ('5c', '0') CRC32 ('5c',NULL)
5 2226203566 2226203566 NULL
Warnings:
Warning 1292 Truncated incorrect INTEGER value: '5c'
Warning 1292 Truncated incorrect INTEGER value: '5c'
Warning 1292 Truncated incorrect INTEGER value: '5c'
Warning 1292 Truncated incorrect INTEGER value: '5c'
SELECT CRC32C('5c',''),CRC32C('5c',0),CRC32C('5c', '0'),CRC32C('5c',NULL);
CRC32C('5c','') CRC32C('5c',0) CRC32C('5c', '0') CRC32C('5c',NULL)
5 1466896124 1466896124 NULL
Warnings:
Warning 1292 Truncated incorrect INTEGER value: '5c'
Warning 1292 Truncated incorrect INTEGER value: '5c'
Warning 1292 Truncated incorrect INTEGER value: '5c'
Warning 1292 Truncated incorrect INTEGER value: '5c'
SELECT CRC32('MariaDB',NULL),CRC32C('MariaDB',NULL);
CRC32('MariaDB',NULL) CRC32C('MariaDB',NULL)
NULL NULL
Warnings:
Warning 1292 Truncated incorrect INTEGER value: 'MariaDB'
Warning 1292 Truncated incorrect INTEGER value: 'MariaDB'
SELECT CRC32(CRC32('MySQL'),''),CRC32(CRC32('My'),'SQL'),CRC32(0,'MySQL');
CRC32(CRC32('MySQL'),'') CRC32(CRC32('My'),'SQL') CRC32(0,'MySQL')
3259397556 3259397556 3259397556
SELECT CRC32C(CRC32C('MariaDB'),''),CRC32C(CRC32C('Maria'),'DB'),CRC32C(0,'MariaDB');
CRC32C(CRC32C('MariaDB'),'') CRC32C(CRC32C('Maria'),'DB') CRC32C(0,'MariaDB')
809606978 809606978 809606978
select crc32(0,'My','SQL');
ERROR 42000: Incorrect parameter count in the call to native function 'crc32'
select crc32c(0,'Maria','DB');
ERROR 42000: Incorrect parameter count in the call to native function 'crc32c'
select crc32();
ERROR 42000: Incorrect parameter count in the call to native function 'crc32'
select crc32c();
ERROR 42000: Incorrect parameter count in the call to native function 'crc32c'
select crc32('' as empty);
ERROR 42000: Incorrect parameters in the call to native function 'crc32'
select crc32c('' as empty);
ERROR 42000: Incorrect parameters in the call to native function 'crc32c'
select crc32(0, '' as empty);
ERROR 42000: Incorrect parameters in the call to native function 'crc32'
select crc32c(0, '' as empty);
ERROR 42000: Incorrect parameters in the call to native function 'crc32c'
select crc32(0 as zero, '');
ERROR 42000: Incorrect parameters in the call to native function 'crc32'
select crc32c(0 as zero, '');
ERROR 42000: Incorrect parameters in the call to native function 'crc32c'
CREATE TEMPORARY TABLE t
(a CHAR(2), i INT UNSIGNED, c INT UNSIGNED AS (CRC32C(i,a)));
INSERT INTO t (a,i) VALUES ('DB',CRC32C('Maria'));
SELECT * FROM t;
a i c
DB 1253907744 809606978
DROP TEMPORARY TABLE t;
select crc32(4294967296,''), hex(char(4294967296));
crc32(4294967296,'') hex(char(4294967296))
0 00
select crc32(1e100,''), hex(char(1e100));
crc32(1e100,'') hex(char(1e100))
4294967295 FFFFFFFF
select crc32(10.11,''), hex(char(10.11));
crc32(10.11,'') hex(char(10.11))
10 0A
select crc32(-1,''), hex(char(-1));
crc32(-1,'') hex(char(-1))
4294967295 FFFFFFFF
select crc32('',''), hex(char(''));
crc32('','') hex(char(''))
0 00
Warnings:
Warning 1292 Truncated incorrect INTEGER value: ''
Warning 1292 Truncated incorrect INTEGER value: ''
select crc32(429496729656755555555555555555555555555555555555555555555555555555555555555555555555555,'a') as x;
x
3310005809
Warnings:
Warning 1916 Got overflow when converting '' to DECIMAL. Value truncated
Warning 1916 Got overflow when converting '99999999999999999999999999999999999999999999999999999999999999999' to INT. Value truncated
DROP TABLE IF EXISTS t;
Warnings:
Note 1051 Unknown table 'test.t'
CREATE TABLE t(a INT, b VARCHAR(2));
INSERT INTO t VALUES (1,'a'), (2,'qw'), (1,'t'), (3,'t');
SELECT crc32(SUM(a)) FROM t;
crc32(SUM(a))
1790921346
SELECT crc32(AVG(a)) FROM t GROUP BY b;
crc32(AVG(a))
768278432
2875100430
2875100430
SELECT crc32(MAX(b)) FROM t GROUP BY a;
crc32(MAX(b))
2238339752
3114057431
2238339752
SELECT crc32(SUM(a)),crc32c(SUM(a)) FROM t;
crc32(SUM(a)) crc32c(SUM(a))
1790921346 3058990603
SELECT crc32(AVG(a)),crc32c(AVG(a)) FROM t GROUP BY b;
crc32(AVG(a)) crc32c(AVG(a))
768278432 1816172052
2875100430 1492934094
2875100430 1492934094
SELECT crc32(MAX(b)),crc32c(MAX(b)) FROM t GROUP BY a;
crc32(MAX(b)) crc32c(MAX(b))
2238339752 3833565251
3114057431 4173859780
2238339752 3833565251
SELECT a, b, crc32(a) FROM t GROUP BY a,b HAVING crc32(MAX(a))=450215437;
a b crc32(a)
2 qw 450215437