sqoop import writes NULL when reading Null values from source table

[#1]

when importing data from sybase all (NULL) values from sybase are written as null strings in the hdfs files

I really want sqoop not to write anything when source contains (NULL) values is that tpossible ?

sqoop import "-Dorg.apache.sqoop.splitter.allow_text_splitter=true" \
--driver net.sourceforge.jtds.jdbc.Driver \
--connect jdbc:jtds:sybase://127.0.0.1:4000/BAS_csrp \
--username xxxx \
--P \
--query "select  cpr_nr  ,
    csrp_koersel_dto       ,
    haendelse_kod            ,
    nyt_cpr_nr               ,
    omplart_kod               ,
    status_kod                ,
    umynd_kod                 ,
    umynd_ins_koersel_dto  ,
    umynd_del_koersel_dto  ,
    pers_nvn                 ,
    flyt_dto               ,
    adr_aendr_aarsag_kod      ,
    adr_bskyt_kod             ,
    adr_art_kod               ,
    bopael_kom_kod            ,
    vej_kod                    ,
    tsr_nr                   ,
    co_nvn                   ,
    adr1                     ,
    vej_nvn                  ,
    hus_nr                    ,
    hus_bogst                 ,
    etage_nr                  ,
    side_nr                   ,
    doer_nr                   ,
    by_nvn                   ,
    post_nr                  ,
    post_by                  ,
    aegtf_fra_dto            ,
    aegtf_til_dto             ,
    aegtf_cpr_nr             ,
    civst_fra_dto          ,
    civst_til_dto          ,
    civst_kod                 ,
    doed_kod                  ,
    doed_dto               ,
    genopliv_kod              ,
    genopliv_dto           ,
    kirke_fra_dto               ,
    kirke_til_dto               ,
    kirke_skat_kod           ,
    far_cpr_nr               ,
    mor_cpr_nr               ,
    pbs1_fra_dto           ,
    pbs1_til_dto           ,
    pbs2_fra_dto           ,
    pbs2_til_dto           ,
    udl_adr1                 ,
    udl_adr2                 ,
    udl_adr3                 ,
    udl_adr4                 ,
    udl_adr5                 ,
    kontakt_adr1             ,
    kontakt_adr2             ,
    kontakt_adr3             ,
    kontakt_adr4             ,
    kontakt_adr5             ,
    supp_adr1                ,
    supp_adr2                ,
    supp_adr3                ,
    emailadr                ,
    mobiltlfnr               ,
    stabokod                  ,
    motagdto_sag           ,
    efterbskdto              ,
    notattkst              ,
    ibertperskod            ,
    senr_1                   ,
    pernr_1                  ,
    fradto_1               ,
    tildto_1               ,
    foskod_1                 ,
    ibertperskod_1          ,
    senr_2                   ,
    pernr_2                  ,
    fradto_2               ,
    tildto_2               ,
    foskod_2                 ,
    ibertperskod_2a          ,
    senr_3                   ,
    pernr_3                  ,
    fradto_3               ,
    tildto_3               ,
    foskod_3                 ,
    ibertperskod_3a          ,
    pers_pernr               ,
    pers_omvalgdto           ,
    pers_fradto            ,
    pers_tildto            ,
    pers_fosskapct           ,
    pers_ibertperskod        ,
    fri_pernr                ,
    fri_fradto             ,
    fri_tildto             ,
    fri_ambifriko            ,
    fri_ibertperskod         ,
    uden_ordnnr_1            ,
    uden_pernr_1             ,
    uden_fradto_1          ,
    uden_til_dto_1         ,
    uden_ibertperskod_1b     ,
    uden_notat_tekst_1     ,
    uden_ordnnr_2            ,
    uden_pernr_2             ,
    uden_fradto_2          ,
    uden_til_dto_2         ,
    uden_ibertperskod_2b     ,
    uden_notat_tekst_2     ,
    uden_ordnnr_3            ,
    uden_pernr_3             ,
    uden_fradto_3          ,
    uden_til_dto_3         ,
    uden_ibertperskod_3b     ,
    uden_notat_tekst_3     ,
    pal_ordnnr               ,
    pal_pernr                ,
    pal_fradto             ,
    pal_tildto             ,
    ibertperskod_2          ,
    notattkst_1            ,
    pernr_fripens_1          ,
    se_nr_fripens_1                  ,
    policektonr_1           ,
    fri_fra_dto_1          ,
    fri_til_dto_1          ,
    skatfri_1               ,
    ibertperkod_fri_1       ,
    notat_fri_1            ,
    pernr_fripens_2          ,
    se_nr_fripens_2                  ,
    policektonr_2           ,
    fri_fra_dto_2          ,
    fri_til_dto_2          ,
    skatfri_2               ,
    ibertperkod_fri_2       ,
    notat_fri_2            ,
    notattkst_3              ,
    pernr_fripens_3          ,
    policektonr_3           ,
    fri_fra_dto_3          ,
    fri_til_dto_3          ,
    skatfri_3               ,
    ibertperkod_fri_3       ,
    notat_fri_3            ,
    vandre_fra_dto         ,
    vandre_til_dto         ,
    ibertperkod_vandre      ,
    notat_vandre           ,
    digital_fra_dto        ,
    digital_til_dto         from csrp_total_bas where CAST(csrp_koersel_dto as DATE)<'2017-04-07' AND \$CONDITIONS" \
--fields-terminated-by '\t' \
--split-by cpr_nr \
--target-dir /tmp/test/sqoop/csrp/

[#2]

Hi Simon, you can try some of the import control options, you can find them here - https://sqoop.apache.org/docs/1.4.3/SqoopUserGuide.html - i.e - The --null-string and --null-non-string arguments are optional.\ If not specified, then the string "null" will be used.

[#3]

Hi Dennis, Thank you very much that worked

[#4]

Hi Dennis,

Even though I declared --null-string as --null-string '\\N' in the sqoop import synatax. still i am seeing "null" string value for all string fields where value is null in source schma. can you please provide any solution to it.

below is my sqoop import syntax.

import -Dhadoop.security.credential.provider.path=${jceks_loc} --password-alias ${passwordAlias} --username ${userName} --connect ${connection} --table ${sourceSchema}.${sourceTable} --hive-import --hive-table ${hiveTable} --target-dir ${hdfsDir} --fields-terminated-by "|" --delete-target-dir --null-string '\\N' -m 1

Thanks,

Brahma