What is the shaping range of 32-bit and 64-bit in PHP and MySql
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A byte has 8 bits, so the 32-bit int type occupies 32 bits / 8 bits = 4 bytes, and the 64-bit int type occupies 64 bits / 8 bits = 8 bytes.
32-bit, 64-bit unsigned integer maximum:
2 ^ 64-1 = 18446744073709551615
2 ^ 32-1 = 4294967295
32-bit, 64-bit signed integer maximum:
(2 ^ 32) / 2-1 = 2147483647
(2 ^ 64) / 2-1 = 9223372036854775807
Minus 1 is because the integer includes 0.
The value of 64-bit Ubuntu 14.04 PowerPoint inscribed Max is 9223372036854775807, which is the same as the maximum value of signed bigint in MySQL.
The value of 32-bit Ubuntu 14.04 is 2147483647, which is the same as the maximum value of signed int in MySQL.
Echo date ('Y-m-d echo date, PHP_INT_MAX); return 2038-01-19 11:14:07
Echo strtotime ('2038-01-19 1111 14 07'); return 2147483647
Echo strtotime ('2038-01-19 11 / 11 / 14 / 14 / 08'); null is returned under 32 bits
That is, the maximum time () of PHP on 32-bit systems can only return a timestamp of 2038-01-19 11:14:07.
Field type: `posted` int (10) unsigned NOT NULL DEFAULT'0'
On 32-bit MySQL (as well as 64-bit MySQL), inserting a number larger than the maximum of 32-bit unsigned int type 2 ^ 32-1 = 4294967295 will cause an error:
UPDATE `punbb`.`pb _ topics`SET `posted` = '4294967296' WHERE `pb_ topics`.`id` = 1
Warning: # 1264 Out of range value for column 'posted' at row 1
However, MySQL can store 64-bit integers with an 8-byte bigint type.
Data type
LP64
ILP64
LLP64
ILP32
LP32
Char
eight
eight
eight
eight
eight
Short
sixteen
sixteen
sixteen
sixteen
sixteen
_ int32
N/A
thirty-two
N/A
N/A
N/A
Int
thirty-two
sixty-four
thirty-two
thirty-two
sixteen
Long
sixty-four
sixty-four
thirty-two
thirty-two
thirty-two
Long long
N/A
N/A
sixty-four
N/A
N/A
Pointer
sixty-four
sixty-four
sixty-four
thirty-two
thirty-two
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