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mysql> select ABS(2);
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mysql> select ABS(-32);
-> 32
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SIGN(X)
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mysql> select SIGN(-32);
-> -1
mysql> select SIGN(0);
-> 0
mysql> select SIGN(234);
-> 1
MOD(N,M)
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mysql> select MOD(234, 10);
-> 4
mysql> select 253 % 7;
-> 1
mysql> select MOD(29,9);
-> 2
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FLOOR(X)
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mysql> select FLOOR(1.23);
-> 1
mysql> select FLOOR(-1.23);
-> -2
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CEILING(X)
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mysql> select CEILING(1.23);
-> 2
mysql> select CEILING(-1.23);
-> -1
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ROUND(X)
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mysql> select ROUND(-1.23);
-> -1
mysql> select ROUND(-1.58);
-> -2
mysql> select ROUND(1.58);
-> 2
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ROUND(X,D)
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mysql> select ROUND(1.298, 1);
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mysql> select ROUND(1.298, 0);
-> 1
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EXP(X)
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mysql> select EXP(2);
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mysql> select EXP(-2);
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