hadoop - Apache Pig:在Pig中处理数据类型时面临问题

Question

处理字段qty的数据类型并在同一字段上执行SUM时遇到问题。下面是代码。我将qty转换为double，但仍然收到下面提到的错误。有人可以帮我理解这个问题，如果可能的话，一个解决方案？

A_test1 = load'EXT_OO_IMP' USING PigStorage('\u0001') AS (it: chararray,loc: chararray,qty: chararray,scheddate: chararray,udc_cta_no: chararray,udc_imp_pack_qty: chararray,udc_imp_ready_dt: chararray,udc_imp_ref_no: chararray,udc_ord_sys_cd: chararray,udc_source: chararray,udc_sply_typ: chararray,udc_vend_pack_id: chararray,udc_purch_stg: chararray,srs_pack_flow_indicator_cd: chararray,it_type_cd: chararray,source_owner_cd: chararray,nks_id: chararray,alloc_replen_cd: chararray);

----- ext_oo_import: {it: chararray,loc: chararray,qty: chararray,scheddate: chararray,udc_cta_no: chararray,udc_imp_pack_qty: chararray,udc_imp_ready_dt: chararray,udc_imp_ref_no: chararray,udc_ord_sys_cd: chararray,udc_source: chararray,udc_sply_typ: chararray,udc_vend_pack_id: chararray,udc_purch_stg: chararray,srs_pack_flow_indicator_cd: chararray,it_type_cd: chararray,source_owner_cd: chararray,nks_id: chararray,alloc_replen_cd: chararray}

----- ##############  ##############  ##############

import_on_order = 
        FOREACH A_test1
        GENERATE
            loc,
            it,
            nks_id,
            (double)(qty is NULL ? 0 : qty) as qty:double,
            scheddate,
            ' ' AS order_source,
            ' ' AS chs_it_type_cd;

describe import_on_order;

----- import_on_order: {loc: chararray,it: chararray,nks_id: chararray,qty: int,scheddate: chararray,order_source: chararray,chs_it_type_cd: chararray}


grp_import_on_order = GROUP import_on_order BY (loc,it,nks_id,scheddate,order_source,chs_it_type_cd);


describe grp_import_on_order;

----- grp_import_on_order: {group: (loc: chararray,it: chararray,nks_id: chararray,scheddate: chararray,order_source: chararray,chs_it_type_cd: chararray),import_on_order: {(loc: chararray,it: chararray,nks_id: chararray,qty: int,scheddate: chararray,order_source: chararray,chs_it_type_cd: chararray)}}



------------------------------- STORE TO FILE ---------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------

work__idrp_import_on_order =
                            FOREACH grp_import_on_order 
                            GENERATE    group.loc AS loc,
                                        group.it AS it,
                                        group.nks_id AS nks_id,
                                        SUM(import_on_order.qty) AS qty,
                                        group.scheddate AS scheddate,
                                        group.order_source AS order_source,
                                        group.chs_it_type_cd AS chs_it_type_cd;

describe work__idrp_import_on_order;

----- work__idrp_import_on_order: {loc: chararray,it: chararray,nks_id: chararray,qty: int,scheddate: chararray,order_source: chararray,chs_it_type_cd: chararray}

import_on_order_rp = 
        FOREACH ext_oo_import
        GENERATE
            it AS chs_it,
            loc AS chs_loc,
            (qty is NULL ? 0 : qty) as qty:double,
            scheddate AS current_due_dt, 
            ' ' AS order_source,
            'V' AS source_type_cd,
            udc_sply_typ AS sply_typ,
            udc_ord_sys_cd AS ord_sys_cd;

2019-01-31 09:03:30,819 [main] ERROR org.apache.pig.tools.grunt.GruntParser - ERROR 0: Exception while executing (Name: grp_import_on_order: Local Rearrange[tuple]{tuple}(false) - scope-1095 Operator Key: scope-1095): org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: work__idrp_import_on_order: New For Each(false,false)[bag] - scope-1078 Operator Key: scope-1078): org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: Pre Combiner Local Rearrange[tuple]{Unknown} - scope-1097 Operator Key: scope-1097): org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: import_on_order: New For Each(false,false,false,false,false,false,false)[bag] - scope-977 Operator Key: scope-977): org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: ext_oo_import: New For Each(false,false,false,false,false)[bag] - scope-957 Operator Key: scope-957): org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: New For Each(false,false,false,false,false)[bag] - scope-945 Operator Key: scope-945): org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing [POCast (Name: Cast[double] - scope-926 Operator Key: scope-926) children: [[POProject (Name: Project[chararray][2] - scope-925 Operator Key: scope-925) children: null at []]] at []]: java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.String Details at logfile: /logs/hdidrp/pig/pig_1548942743751.log 2019-01-31 09:03:30,849 [main] INFO org.apache.hadoop.conf.Configuration.deprecation - fs.default.name is deprecated. Instead, use fs.defaultFS 2019-01-31 09:03:31,012 [main] WARN org.apache.pig.PigServer - Encountered Warning IMPLICIT_CAST_TO_DOUBLE 1 time(s). import_on_order_rp: {shc_item: chararray,shc_loc: chararray,qty: double,current_due_dt: chararray,order_source: chararray,source_type_cd: chararray,sply_typ: chararray,ord_sys_cd: chararray} 2019-01-31 09:03:31,179 [main] ERROR org.apache.pig.tools.grunt.GruntParser - ERROR 0: Exception while executing (Name: grp_import_on_order: Local Rearrange[tuple]{tuple}(false) - scope-1095 Operator Key: scope-1095): org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: work__idrp_import_on_order: New For Each(false,false)[bag] - scope-1078 Operator Key: scope-1078): org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: Pre Combiner Local Rearrange[tuple]{Unknown} - scope-1097 Operator Key: scope-1097): org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: import_on_order: New For Each(false,false,false,false,false,false,false)[bag] - scope-977 Operator Key: scope-977): org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: ext_oo_import: New For Each(false,false,false,false,false)[bag] - scope-957 Operator Key: scope-957): org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: New For Each(false,false,false,false,false)[bag] - scope-945 Operator Key: scope-945): org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing [POCast (Name: Cast[double] - scope-926 Operator Key: scope-926) children: [[POProject (Name: Project[chararray][2] - scope-925 Operator Key: scope-925) children: null at []]] at []]: java.lang.ClassCastException: java.lang.Integer cannot be cast to java.lang.String

Answer 1

在查看了代码之后，无法进入第一条语句，您正在加载数据并执行转换步骤，但是在最后一步中，为什么再次转换字符串类型的第一个数据集，并在处理该数据集时却给出异常。

import_on_order_rp = FOREACH ext_oo_import GENERATE it AS chs_it, loc AS chs_loc, (qty is NULL ? 0 : qty) as qty:double, scheddate AS current_due_dt, ' ' AS order_source, 'V' AS source_type_cd, udc_sply_typ AS sply_typ, udc_ord_sys_cd AS ord_sys_cd;

看看是否正确。