Just move the case expression into an underlying select clause. On Thu, Jul 13, 2017 at 3:10 PM, Chang Chen <baibaic...@gmail.com> wrote:
> Hi Wenchen > > Yes. We also find this error is caused by Rand. However, this is classic > way to solve data skew in Hive. Is there any equivalent way in Spark? > > Thanks > Chang > > > On Thu, Jul 13, 2017 at 8:25 PM, Wenchen Fan <cloud0...@gmail.com> wrote: > >> It’s not about case when, but about rand(). Non-deterministic expressions >> are not allowed in join condition. >> >> > On 13 Jul 2017, at 6:43 PM, wangshuang <cn_...@qq.com> wrote: >> > >> > I'm trying to execute hive sql on spark sql (Also on spark >> thriftserver), For >> > optimizing data skew, we use "case when" to handle null. >> > Simple sql as following: >> > >> > >> > SELECT a.col1 >> > FROM tbl1 a >> > LEFT OUTER JOIN tbl2 b >> > ON >> > * CASE >> > WHEN a.col2 IS NULL >> > TNEN cast(rand(9)*1000 - 9999999999 as string) >> > ELSE >> > a.col2 END * >> > = b.col3; >> > >> > >> > But I get the error: >> > >> > == Physical Plan == >> > *org.apache.spark.sql.AnalysisException: nondeterministic expressions >> are >> > only allowed in >> > Project, Filter, Aggregate or Window, found:* >> > (((CASE WHEN (a.`nav_tcdt` IS NULL) THEN CAST(((rand(9) * CAST(1000 AS >> > DOUBLE)) - CAST(9999999999L AS DOUBLE)) AS STRING) ELSE a.`nav_tcdt` >> END = >> > c.`site_categ_id`) AND (CAST(a.`nav_tcd` AS INT) = 9)) AND >> (c.`cur_flag` = >> > 1)) >> > in operator Join LeftOuter, (((CASE WHEN isnull(nav_tcdt#25) THEN >> > cast(((rand(9) * cast(1000 as double)) - cast(9999999999 as double)) as >> > string) ELSE nav_tcdt#25 END = site_categ_id#80) && (cast(nav_tcd#26 as >> int) >> > = 9)) && (cur_flag#77 = 1)) >> > ;; >> > GlobalLimit 10 >> > +- LocalLimit 10 >> > +- Aggregate [date_id#7, CASE WHEN (cast(city_id#10 as string) IN >> > (cast(19596 as string),cast(20134 as string),cast(10997 as string)) && >> > nav_tcdt#25 RLIKE ^[0-9]+$) THEN city_id#10 ELSE nav_tpa_id#21 END], >> > [date_id#7] >> > +- Filter (date_id#7 = 2017-07-12) >> > +- Join LeftOuter, (((CASE WHEN isnull(nav_tcdt#25) THEN >> > cast(((rand(9) * cast(1000 as double)) - cast(9999999999 as double)) as >> > string) ELSE nav_tcdt#25 END = site_categ_id#80) && (cast(nav_tcd#26 as >> int) >> > = 9)) && (cur_flag#77 = 1)) >> > :- SubqueryAlias a >> > : +- SubqueryAlias tmp_lifan_trfc_tpa_hive >> > : +- CatalogRelation `tmp`.`tmp_lifan_trfc_tpa_hive`, >> > org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe, [date_id#7, >> chanl_id#8L, >> > pltfm_id#9, city_id#10, sessn_id#11, gu_id#12, >> nav_refer_page_type_id#13, >> > nav_refer_page_value#14, nav_refer_tpa#15, nav_refer_tpa_id#16, >> > nav_refer_tpc#17, nav_refer_tpi#18, nav_page_type_id#19, >> nav_page_value#20, >> > nav_tpa_id#21, nav_tpa#22, nav_tpc#23, nav_tpi#24, nav_tcdt#25, >> nav_tcd#26, >> > nav_tci#27, nav_tce#28, detl_refer_page_type_id#29, >> > detl_refer_page_value#30, ... 33 more fields] >> > +- SubqueryAlias c >> > +- SubqueryAlias dim_site_categ_ext >> > +- CatalogRelation `dw`.`dim_site_categ_ext`, >> > org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe, >> [site_categ_skid#64L, >> > site_categ_type#65, site_categ_code#66, site_categ_name#67, >> > site_categ_parnt_skid#68L, site_categ_kywrd#69, leaf_flg#70L, >> sort_seq#71L, >> > site_categ_srch_name#72, vsbl_flg#73, delet_flag#74, etl_batch_id#75L, >> > updt_time#76, cur_flag#77, bkgrnd_categ_skid#78L, bkgrnd_categ_id#79L, >> > site_categ_id#80, site_categ_parnt_id#81] >> > >> > Does spark sql not support syntax "case when" in JOIN? Additional, my >> spark >> > version is 2.2.0. >> > Any help would be greatly appreciated. >> > >> > >> > >> > >> > -- >> > View this message in context: http://apache-spark-developers >> -list.1001551.n3.nabble.com/SQL-Syntax-case-when-doesn-t-be- >> supported-in-JOIN-tp21953.html >> > Sent from the Apache Spark Developers List mailing list archive at >> Nabble.com. >> > >> > --------------------------------------------------------------------- >> > To unsubscribe e-mail: dev-unsubscr...@spark.apache.org >> > >> >> >> --------------------------------------------------------------------- >> To unsubscribe e-mail: dev-unsubscr...@spark.apache.org >> >> > -- Herman van Hövell Software Engineer Databricks Inc. hvanhov...@databricks.com +31 6 420 590 27 databricks.com [image: http://databricks.com] <http://databricks.com/> [image: Announcing Databricks Serverless. The first serverless data science and big data platform. Watch the demo from Spark Summit 2017.] <http://go.databricks.com/announcing-databricks-serverless>
