CASE <运算式> WHEN <运算式> THEN <运算式> WHEN <运算式> THEN <运算式> [ELSE <运算式>] END 如: update employee set e_wage = case when job_level = ’1’ then e_wage*1.08 when job_level = ’2’ then e_wage*1.07 when job_level = ’3’ then e_wage*1.06 else e_wage*1.05 ...
The size of each log file in a log group. The default is 5MB. The larger the value, the less checkpoint flush activity is needed in the buffer pool, saving disk I/O. But large log files also mean that recovery will be slower in case of a crash. 根据MySQL手册,推荐值是innodb_buffer_...
SELECT (CASE WHEN c.in_force_dateISNOT NULL THEN (CASE WHEN a.mio_date>=c.in_force_dateTHENa.mio_date ELSE c.in_force_date END ) WHEN c.in_force_dateISNULL THEN (CASE WHEN a.mio_date>=a.plnmio_dateTHENa.mio_date ELSE a.plnmio_date END ) ELSE a.mio_date END ) mio_date...
-- sqlldr USERID=scott/tiger CONTROL=ulcase7.ctl LOG=ulcase7.log -- -- 3. After you have run the case study and finished with it, you -- must run the ulcase7e.sql script before you can successfully -- run other case studies. This script drops the INSERT trigger -- and the glob...
本机编译的 T-SQL 模块支持 CASE 表达式。 下面的示例演示了在查询中使用 CASE 表达式的方法。 -- Query using a CASE expression in a natively compiled stored procedure. CREATE PROCEDURE dbo.usp_SOHOnlineOrderResult WITH NATIVE_COMPILATION, SCHEMABINDING, EXECUTE AS O...
类20 - 未找到CASE 20000 未找到CASE(CASE_NOT_FOUND) 类21 - 势违例 21000 势违例(CARDINALITY_VIOLATION) 类22 - 数据异常 22000 数据异常(DATA_EXCEPTION) 2202E 数组下标错误(ARRAY_SUBSCRIPT_ERROR) 22021 字符不被计算机命令系统识别(CHARACTER_NOT_IN_REPERTOIRE) 22008 日期时间字段溢出(DATETIME_FIELD_OVE...
DECLARE @local_variable (Transact-SQL)可以使用所有内存中 OLTP 支持的数据类型以及内存优化表类型。 可将变量声明为 NULL 或 NOT NULL。 SET @local_variable (Transact-SQL) TRY...CATCH (Transact-SQL) 要优化性能,请对整个本机编译的 T-SQL 模块使用单个 TRY/CATCH ...
識別需要漸進式維護的相依表格,並針對這些相依表格發出使用 IMMEDIATE CHECKED 選項的 SET INTEGRITY 陳述式,然後重新發出失敗的 ALTER TABLE 陳述式。 下列查詢可識別需要漸進式維護的相依表格,其中 <schema name> 是 table-name 的限定元,而 是 table-name 的表格名稱部分。 WITH DEP_CNT(TOTAL_DEP) AS...
select c1 end from ( select 0 c1 end from src union all select case when key = 0 then 0 else 1/key end) r; small.table.exceeds.mem.limit 旧版MaxCompute支持Multi-way Join优化,多个Join如果有相同Join Key,会合并到一个Fuxi Task中执行,比如下面例子中的J4_1_2_3_Stg1: explain select t1...
CASE can also be used in a SET statement, to assign a value to a variable: SET DATEFIRST 1DECLARE @isitfridayyet VARCHAR(100SET @isitfridayyet=CASE WHENDATEPART(WEEKDAY,GETDATE())=5 THEN'It''s Friday!'ELSE'It''s not yet Friday...'END ...