CREATEORREPLACEFUNCTION"ap"."get_random_areacode"()RETURNS"pg_catalog"."varchar"AS$BODY$DECLARE-- start_int ALIAS FOR $1;arrVARCHAR[] :=ARRAY(SELECTarea_idFROMap.dim_region_code) ;BEGINRETURNarr[ap.get_random_number(1,array_length(arr,1))];END; $BODY$LANGUAGEplpgsql VOLATILE COST100
CREATEPROCEDUREGenerateOrderNumberASBEGINDECLARE@OrderNumberVARCHAR(14)WHILE1=1BEGINSET@OrderNumber=dbo.GenerateRandomNumber()IFNOTEXISTS(SELECT1FROMORDERSWHEREorder_number=@OrderNumber)BEGINBREAKENDENDINSERTINTOORDERS(customer_id,order_number,order_date)VALUES(@CustomerId,@OrderNumber,GETDATE())SELECT@Order...
SELECTFLOOR(number)FROMtable_nameWHEREcondition;SELECTCEILING(number)FROMtable_nameWHEREcondition; 其中,number为要取整的数,condition为筛选条件。例如,对students表中的age列进行向下取整: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 SELECTFLOOR(age)FROMstudents; ROUND函数 ROUND函数用于对一个数进行四舍...
指定RANDOM 關鍵字以及 RANDOM 關鍵字所支援資料類型的直欄,以重新提交 CREATE INDEX 陳述式。 發出ALTER TABLE 陳述式來變更直欄,以將直欄識別為 FOR BIT DATA,並重組表格,然後重新提交 CREATE INDEX 建立索引。 2 指定RANDOM 關鍵字以及 RANDOM 關鍵字所支援資料類型的直欄,以重新提交 CREATE INDEX 陳述式。
from (select floor(random() * (max(id) - min(id))) as id from test_d) as ma inner join test_d as d on ma.id = d.id; 通过以上方法来做的情况下,每次生产一个随机记录 1.1秒 而 不采用这样的方法直接使用最上面的方法,则需要2.2秒,以上测试时在100万数据行中进行测试的。
RandomNumber --- 0.34344339282376501 The output of the RAND function will always be a value between 0 and 1. If you want to generate a random integer number, all you have to do is multiply it by the maximum value you want generated and then get rid of the decimal places. One way of ...
D: Slow and inefficient as the number of manipulations on the text exceeds.4. Using Random CHAR-> Using Loop to build a flexible string lengthBasic IdeaWe are using a UDF to create a single random string. the function get 2 parameters: (A) the maximum length of the String (B) Do we...
random_number.sh - prints a random integer between two integer arguments (inclusive) random_string.sh - prints a random alphanumeric string of a given length shields_embed_logo.sh - base64 encodes a given icon file or url and prints the logo=... url parameter you need to add the shields...
在UPDATE或INSERT查询中使用RAND()函数时,所有受影响的行都会获得相同的值。 示例 以下示例将产生由RAND()函数生成的四个不同的随机数。 SQL DECLARE@counterSMALLINT;SET@counter =1; WHILE @counter < 5BEGINSELECTRAND() Random_NumberSET@counter = @counter +1END; GO ...
This will create a random number between 1 and 9999 SET @Lower = 1 The lowest random number SET @Upper = 9999 The highest random number SELECT @Random = ROUND(((@Upper - @Lower -1) * RAND() + @Lower), 0) SET @Final = 'S-' + Right(Year(getDate()),2) + RIGHT('0' + RT...