几种整形数据类型的长度
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类型 占用空间(字节) 最小值(带符号的/无符号的) 最大值(带符号的/无符号的)
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TINYINT 1 -128 127
0 255
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SMALLINT 2 -32768 32767
0 65535
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MEDIUMINT 3 -8388608 8388607
0 16777215
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int 4 -2147483648 2147483647
0 4294967295
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BIGINT 8 -9223372036854775808 9223372036854775807
0 18446744073709551615
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注:1字节=8位