coalesce teradata

ArticleDirectory Basic syntax Examples Coalesce and nullif Functions Conclusion The difference between the expression and the as expression after the case and the end is the most obvious -- Oracle Select T_cx_orders. * , Case When Fissendmail = 1 Then Ffilepath Else ' . ' End Downloadpath From T_cx_orders Where Fuserid = ' Aaa613 ' Order By Finne

displayed in the result set is 0.00. USE pubsGOSelect substring (title, 1, 15) AS Title, type AS Type,ISNULL (price, 0.00) AS PriceFROM titlesGO The following is the result set: Title Type Price-----------------------------------------------------The Busy Execut business 19.99Cooking with Co business 11.95You Can Combat business 2.99Straight Talk A business 19.99Silicon Valley mod_cook 19.99The Gourmet Mic mod_cook 2.99The Psychology UNDECIDED SQL ISNULL (), NVL (), IFNULL (), and

For MySQLLeftJOIN, specify the NULL column to return specific values. for details, see bitsCN.com. The coalesce function can accept multiple parameters and returns the first non-NULL value of these parameters. if all the provided parameters are NULL, NULL is returned.The ifnull function is the same as the coalesce function, but only two parameters can be accepted.The if function accepts three parameters, w

out data that does not meet the criteria and returns a new RDD def filter (f:t = Boolean): rdd[t] = withscope {Val cleanf = Sc.clean (f)New Mappartitionsrdd[t, T] (This(context, PID, iter) = Iter.filter (CLEANF),Preservespartitioning = True)} 4) Distinct function, remove duplicate elements, return different elements, and return a new RDD def distinct (numpartitions:int) (implicit ord:ordering[t] = null): rdd[t] = withscope {Map (x = (x, null)). Reducebykey ((x, y) = x, n

To create a test table:CREATE OR REPLACE VIEW v asselect NULL as C1, NULL as C2, ' 1 ' as C3, null as C4, ' 2 ' as C5 from dualunion allselect NULL A S C1, NULL as c2, NULL as C3, ' 3 ' as C4, ' 2 ' as C5 from dual; SELECT * from V;If you want to query the value of a column C3, when C3 is empty, display it as 0, in the following two ways:--Use the NVL function select NVL (C3, ' 0 ') C3 from v;--using COALESCE function Select

, characters, and time values. It accepts two parameters-the list of values and options to be tested. The following is an example of using a string: Mysql> SELECT 'C' IN ('A', 'B', 'C', 'D '); + ----------------------------------------------------------- + | 'C' IN ('A', 'B', 'C', 'D') | + ----------------------------------------------------------- + | 1 | + ----------------------------------------------------------- + 1 row in set (0.02 sec) The following example uses numbers: Mysql> SELECT 1 I

Mysql multiple subqueries multiple LEFTJOIN views create bitsCN.com CREATE VIEW `v_noprovide` AS SELECT*FROMtb_sectionWHEREprovide = '0'CREATE VIEW `v_thismonth` AS SELECTts.userId AS id,CONCAT('thismonth:',SUM(ts.amount),'yuan') AS 'thismonth'FROMtb_section AS tsWHEREts.yearMonth = DATE_FORMAT(NOW(), '%Y%m')CREATE VIEW `v_lastmonth` AS SELECTts.userId AS id,CONCAT('lastmonth:',SUM(ts.amount),'yuan') AS 'lastmonth'FROMtb_section AS tsWHEREts.yearMonth = DATE_FORMAT(DATE_SUB(NOW(), INTERVAL 1 MO

; # SELECT city, color, ROUND (SUM (price), 2) AS id_count FROM data1 group by city, color; Data pivoting The "pivot table" function is provided under the insert directory in Excel to summarize data tables by specific dimensions. Mysql does not directly provide the pivot table function. But the same effect is achieved through the case when function. Pivot tables are also commonly used in data classification and summarization, and are more powerful than group. In the following code, set "cit

fromApscheduler.schedulers.backgroundImportBackgroundscheduler, Blockingscheduler fromApscheduler.jobstores.redisImportRedisjobstore fromApscheduler.jobstores.sqlalchemyImportSqlalchemyjobstore fromApscheduler.executors.poolImportThreadpoolexecutor, ProcesspoolexecutordefPrint_args (*args):"""functions to be executed at timed:p Aram args: Parameters: Return:none""" forArginchargs:Print(ARG)#There are two types of thread pool and process pool commonly used by actuatorsThread_pool = Threadpool

The COALESCE function can accept more than one argument and returns the first Non-null value of those arguments, or null if all the supplied arguments are nullThe Ifnull function, like the COALESCE function, can only accept two parametersThe IF function accepts three parameters, which is similar to the ternary (?:) function, that is, the first argument is not null and is not 0 o'clock, the second argument i

1. Optimization? Why? How? When? What? "Spark applications also need to be optimized. "Many people may have this question," not already have code generators, executive optimizer, pipeline or something. ”。 Yes, Spark does have some powerful built-in tools to make your code faster when it executes. But if everything depends on the tools, framework to do, I think that can only illustrate two questions: you are only aware of the framework, but not the reason why; it seems you are only divert, with

');+-----------------------------+| ' C ' in (' A ', ' B ', ' C ', ' d ') |+-----------------------------+| 1 |+-----------------------------+1 row in Set (0.02 sec) The following example uses a number: The following are the referenced contents:Mysql> SELECT 1 in (3,4,5);+--------------+| 1 in (3,4,5) |+--------------+| 0 |+--------------+1 row in Set (0.00 sec) Coalesce The coa