SELECTLEFT('SQL Tutorial',3)ASExtractString; Try it Yourself » Definition and Usage The LEFT() function extracts a number of characters from a string (starting from left). Syntax LEFT(string,number_of_chars)
DECLARE @string_to_trim varchar(60) 1. SET @string_to_trim = ' Five spaces are at the beginning of this 1. string.' 1. SELECT 'Here is the string without the leading spaces: ' + 1. LTRIM(@string_to_trim) 1. GO 1. 下面是结果集: --- 1. Here is the string without the lead...
substr('Hello World',-3,3)//返回结果为 'rld' *负数(-i)表示截取的开始位置为字符串右端向左数第i个字符 Oracle数据库中是没有left() 和right() 函数的,若想按照DB2中对应的函数去使用,自己新建两个function即可,方法如下 LEFT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 CREATE OR REPLACE FU...
SELECTLEFT(Name,5)FROMProduction.ProductORDERBYProductID; GO B. Using LEFT with a character string The following example usesLEFTto return the two leftmost characters of the character stringabcdefg. SQL SELECTLEFT('abcdefg',2); GO Here is the result set. ...
Oracle数据库中是没有left() 和right() 函数的,若想按照DB2中对应的函数去使用,自己新建两个function即可,方法如下 LEFT CREATEORREPLACEFUNCTION"LEFT" (strinvarchar2,sublenininteger)returnvarchar2isstrleninteger;beginstrlen :=length(str);ifsublen<=0thenreturn''; ...
left(str,n) Arguments str: String expression to operate on. Can be a constant, column, or function, and any combination of string operators. n: Number of characters to return. Related functions right Viewleftquery example length Returns the number of characters in a string. ...
B. Using LEFT with a character string The following example uses LEFT to return the two leftmost characters of the character string abcdefg. SELECT LEFT('abcdefg',2) GO Here is the result set. -- ab (1 row(s) affected) See Also ...
LEFT(arg, len) String of the length len with the len left characters of arg (ignoring the trailing blanks). The value of len cannot be greater than the length of arg. x - LENGTH(arg) Number of characters in arg ignoring trailing blanks. x x LPAD(arg, len, src) String of the lengt...
(numeric_expression)绝对值SELECTABS(-1);--CEILING(numeric_expression)大于或等于指定数值表达式的最小整数SELECTCEILING(2.3);--FLOOR(numeric_expression)小于或等于指定数值表达式的最大整数SELECTFLOOR(2.3);--ROUND(numeric_expression,length[,function])舍入--length 必须是 tinyint、smallint 或 int 类型的...
STRING类型。STRUCT类型对象的成员变量。 返回值说明 返回STRUCT类型对象的成员变量的取值。 示例 --返回hello。 select field(named_struct('f1', 'hello', 'f2', 3), 'f1');FILTER 命令格式 array<T> filter(array<T> , function<T,boolean> <func>) 命令说明 将ARRAY数组a中的元素利用func进行过滤,...