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mysql> select - 2; 
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ABS(X)
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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); 
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EXP(X) 
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mysql> select EXP(2); 
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mysql> select EXP(-2); 
-> 0.


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explaination of mysql/bin/ file

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