function.txt

一个mysql可视化操作工具

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# MySQL-Function-list: used by MySQL-Front on opening a connection.
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# you can add or delete entrys as you want - perhaps you want only
# a few of them shown in the functions-Popup-Menu
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# One or more spaces as first character recognizes the entry as sub-item
# A - represents a seperator
# A | (pipe) indicates that a comment follows
#
Comparison
  GREATEST(X,Y,...)|Returns the largest (maximum-valued) argument. The arguments are compared using the same rules as for LEAST.
  IF(expr1,expr2,expr3)|If expr1 is TRUE (expr1 <> 0 and expr1 <> NULL) then IF() returns expr2, else it returns expr3
  IFNULL(expr1,expr2)|If expr1 is not NULL, IFNULL() returns expr1, else it returns expr2.
  INTERVAL(N,N1,N2,N3,...)|Returns 0 if N < N1, 1 if N < N2 and so on.
  ISNULL(expr)|If expr is NULL, ISNULL() returns 1, otherwise it returns 0.
  LEAST(X,Y,...)|With two or more arguments, returns the smallest (minimum-valued) argument.
  NULLIF(expr1,expr2)|If expr1 = expr2 is true, return NULL else return expr1.
  STRCMP(expr1,expr2)|returns 0 if the strings are the same, -1 if the first argument is smaller than the second according to the current sort order, and 1 otherwise.
Math
  ABS(X)|Returns the absolute value of X.
  ACOS(X)|Returns the arc cosine of X, that is, the value whose cosine is X. Returns NULL if X is not in the range -1 to 1.
  ASIN(X)|Returns the arc sine of X, that is, the value whose sine is X. Returns NULL if X is not in the range -1 to 1.
  ATAN(X)|Returns the arc tangent of X, that is, the value whose tangent is X.
  ATAN2(X,Y)|Returns the arc tangent of the two variables X and Y. It is similar to calculating the arc tangent of Y / X, except that the signs of both arguments are used to determine the quadrant of the result.
  CEILING(X)|Returns the smallest integer value not less than X.
  COS(X)|Returns the cosine of X, where X is given in radians.
  COT(X)|Returns the cotangent of X.
  DEGREES(X)|Returns the argument X, converted from radians to degrees.
  EXP(X)|Returns the value of e (the base of natural logarithms) raised to the power of X.
  FLOOR(X)|Returns the largest integer value not greater than X.
  LOG(X)|Returns the natural logarithm of X.
  LOG10(X)|Returns the base-10 logarithm of X.
  MOD(N,M)|Modulo (like the % operator in C). Returns the remainder of N divided by M.
  PI()|Returns the value of PI.
  POW(X,Y)|Returns the value of X raised to the power of Y.
  POWER(X,Y)|Returns the value of X raised to the power of Y.
  RADIANS(X)|Returns the argument X, converted from degrees to radians.
  RAND(N)|Returns a random floating-point value in the range 0 to 1.0. If an integer argument N is specified, it is used as the seed value.
  ROUND(X,D)|Returns the argument X, rounded to a number with D decimals. If D is 0, the result will have no decimal point. 
  SIGN(X)|Returns the sign of the argument as -1, 0 or 1, depending on whether X is negative, zero, or positive.
  SIN(X)|Returns the sine of X, where X is given in radians.
  SQRT(X)|Returns the non-negative square root of X.
  TAN(X)|Returns the tangent of X, where X is given in radians.
  TRUNCATE(X,D)|Returns the number X, truncated to D decimals. If D is 0, the result will have no decimal point or fractional part.
String
  ASCII(str)|Returns the ASCII code value of the leftmost character of the string str. Returns 0 if str is the empty string. Returns NULL if str is NULL.
  BIN(N)|Returns a string representation of the binary value of N, where N is a longlong (BIGINT) number.
  CHAR(N,...)|interprets the arguments as integers and returns a string consisting of the characters given by the ASCII code values of those integers.
  CHARACTER_LENGTH(str)|Returns the length of the string str.
  CHAR_LENGTH(str)|Returns the length of the string str.
  COALESCE(list)|Returns first non-NULL element in list.
  CONCAT(str1,str2,...)|Returns the string that results from concatenating the arguments.
  CONCAT_WS(separator, str1, str2,...)|stands for CONCAT With Separator and is a special form of CONCAT(). The first argument is the separator for the rest of the arguments
  CONV(N,from_base,to_base)|Converts numbers between different number bases. Returns a string representation of the number N, converted from base from_base to base to_base.
  ELT(N,str1,str2,str3,...)|Returns str1 if N = 1, str2 if N = 2, and so on. Returns NULL if N is less than 1 or greater than the number of arguments. ELT() is the complement of FIELD().
  EXPORT_SET(bits,on,off,[separator,[number_of_bits]])|Returns a string where for every bit set in "bit", you get a "on" string and for every reset bit you get an "off" string. Each string is separated with "separator" (default ",") and only "number_of_bits" (default 64) of "bits" is used.
  FIELD(str,str1,str2,str3,...)|Returns the index of str in the str1, str2, str3, ... list. Returns 0 if str is not found. FIELD() is the complement of ELT().
  FIND_IN_SET(str,strlist)|Returns a value 1 to N if the string str is in the list strlist consisting of N substrings. A string list is a string composed of substrings separated by "," characters.
  FORMAT(X,D)|Formats the number X to a format like "#,###,###.##", rounded to D decimals. If D is 0, the result will have no decimal point or fractional part.
  HEX(N)|Returns a string representation of the hexadecimal value of N, where N is a longlong (BIGINT) number.
  INSERT(str,pos,len,newstr)|Returns the string str, with the substring beginning at position pos and len characters long replaced by the string newstr.
  INSTR(str,substr)|Returns the position of the first occurrence of substring substr in string str
  LCASE(str)|Returns the string str with all characters changed to lowercase according to the current character set mapping (the default is ISO-8859-1 Latin1).
  LEFT(str,len)|Returns the leftmost len characters from the string str.
  LENGTH(str)|Returns the length of the string str.
  LOCATE(substr,str,pos)|Returns the position of the first occurrence of substring substr in string str, starting at position pos.
  LOWER(str)|Returns the string str with all characters changed to lowercase according to the current character set mapping (the default is ISO-8859-1 Latin1).
  LPAD(str,len,padstr)|Returns the string str, left-padded with the string padstr until str is len characters long.
  LTRIM(str)|Returns the string str with leading space characters removed.
  MAKE_SET(bits,str1,str2,...)|Returns a set (a string containing substrings separated by "," characters) consisting of the strings that have the corresponding bit in bits set. str1 corresponds to bit 0, str2 to bit 1, etc. NULL strings in str1, str2, ... are not appended to the result.
  MID(str,pos,len)|Returns a substring len characters long from string str, starting at position pos.
  OCT(N)|Returns a string representation of the octal value of N, where N is a longlong number.
  OCTET_LENGTH(str)|Returns the length of the string str.
  ORD(str)|If the leftmost character of the string str is a multi-byte character, returns the code of multi-byte character by returning the ASCII code value of the character
  POSITION(substr IN str)|Returns the position of the first occurrence of substring substr in string str.
  REPEAT(str,count)|Returns a string consisting of the string str repeated count times. If count <= 0, returns an empty string.