Relationship between characters and mathematical functions
select charset('你好'); select concate('nihao', 'mysql','java'); select concat('你好'); select instr('www.baidu.com', 'baidu'); Select ucase('abc'); Select lcase('ABC'); Select left('abcdefg',3); Select length('abc'); select replace('www.baidu.com', 'baidu', 'qq'); select strcmp('abc','abc'); select strcmp('abc','ABC'); select substring('www.baidu.com ',3,5); select ltrim(' abc'); select rtrim(' abc'); select length rtrim(' abc'); select length (rtrim(' abc')); select abs(1);select abs(-1); select bin(3);select ceiling(1.1); select floor(1.1); select conv(10, 10, 2); select format(2.222333, 0); select hex(10); select least(2, 4, 5, 6, 10); select mod(10, 3) ; select rand(0,10);
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