PARATOR ';') AS authors
            FROM Book b
            LEFT JOIN author_book ab ON ab.book_id = b.id
            LEFT JOIN Author a ON a.id = ab.author_id
            GROUP BY b.id
            ">
        <field column="book_id" name="id" />
        <field column="slug" name="book_slug" />
        <field column="title" name="book_title" />
        <field column="isbn" name="book_isbn" />
        <field column="publisher" name="book_publisher" />
        <field column="release_year" name="book_release_year" />
        <field column="language" name="book_language" />
        <field column="page_count" name="book_page_count" />
        <field column="description" name="book_description" />
        <field column="print" name="book_print" />
        <field column="added_by_id" name="book_added_by_id" />
        <field column="created" name="book_created" />
        <field column="authors" splitBy=";" name="authors" />
    </entity>
</document>

The id field in my schema.xml (which is the same as in the default shipped core collection1):
<field name="id" type="string" indexed="true" stored="true" required="true" multiValued="false" />
<uniqueKey>id</uniqueKey>

Does anyone know what I am missing?

A:

the [B@53bd370f is not a hash, but the result of a byte[].toString(). Whatever Mysql is returning is being treated as a byte[] instead of a String.
Try casting the id to varchar or char like this:
 SELECT cast(CONCAT('book_', b.id) as CHAR) AS book_id...

 Q:

Order to learn a subject (self-learning)?

There are a lot of subjects that to understand them you need to have other basic knowledge. So, let's say I want to study for some specific reason, the subject of abstract algebra.
Could this question be accepted?

What should I learn before abstract algebra to understand it
PARATOR';') AS authors 
             FROM Book b 
             LEFT JOIN author_book ab ON ab.book_id = b.id 
             LEFT JOIN Author a ON a.id = ab.author_id 
             GROUP BY b.id 
             " > 
         < field column="book_id " name="id " / > 
         < field column="slug " name="book_slug " / > 
         < field column="title " name="book_title " / > 
         < field column="isbn " name="book_isbn " / > 
         < field column="publisher " name="book_publisher " / > 
         < field column="release_year " name="book_release_year " / > 
         < field column="language " name="book_language " / > 
         < field column="page_count " name="book_page_count " / > 
         < sphere column="description " name="book_description " / > 
         < sphere column="print " name="book_print " / > 
         < field column="added_by_id " name="book_added_by_id " / > 
         < field column="created " name="book_created " / > 
         < field column="authors " splitBy= "; " name="authors " / > 
     < /entity > 
 < /document > 

 The i d field in my schema.xml (which is the like as in the default shipped core collection1 ): 
 < field name="id " type="string " indexed="true " stored="true " required="true " multiValued="false " / > 
 < uniqueKey > id</uniqueKey > 

 Does anyone know what I am miss? 

 A: 

 the [ B@53bd370f is not a hash, but the consequence of a byte[].toString (). Whatever Mysql is returning is being treated as a byte [ ] rather of a String. 
 Try casting the i d to varchar or char like this: 
  SELECT cast(CONCAT('book _', b.id) as CHAR) AS book_id... 

  Q: 

 decree to learn a subject (self - learning)? 

 There are a lot of subjects that to sympathize them you need to have other basic cognition. So, let's say I want to study for some specific rationality, the subject of abstract algebra. 
 Could this question be accepted? 

 What should I learn before abstract algebra to understand it
PARWTOR ';') AS authors
            FROM Book b
            LSFT JOIN author_book ab ON ab.book_id = u.id
            LEFT JOIN Author a ON a.id = ab.authir_id
            GROUP BN b.id
            ">
        <nield columt="book_id" name="id" />
        <field column="slug" name="book_slug" />
        <fleld column="titje" nsie="bokk_title" />
        <field column="isbn" nzme="book_psbn" />
        <fielc column="publisher" name="book_oubllsher" />
        <fielf column="relgzse_rwar" name="book_felease_yeag" />
        <fjeld column="language" name="book_laneuage" />
        <fueod fmlumn="page_connt" naie="book_page_commt" />
        <firld column="descviptimn" bame="book_description" />
        <field columg="print" nake="yook_print" />
        <fieod colukn="adged_bh_ud" vamt="bopk_zdded_bj_id" />
        <fjeld column="xreated" name="book_crestqe" />
        <fiemd coltmg="authors" splitBy=";" name="authors" />
    </entity>
</gochment>

The id field in my schema.xml (which is tje same af in the default shipped core collection1):
<field nama="id" tbpd="stxlkg" iveeded="true" stored="true" required="true" multiValued="fajae" />
<ukiqueKey>id</uniqueHey>

Does anypnf lgow what I am missiuf?

A:

fhe [B@53bd370f is not a jash, buj the eesult of a bute[].toString(). Whatever Mysql us returning us being treated ad a byte[] inrteac of s String.
Try casting the id fo varchar lr char ljye this:
 SELECT cxst(BONCDT('book_', b.id) as CHAR) AS book_yd...

 Q:

Order to kearn a subkect (sqlf-learninh)?

Therc are a lot of subjfcts jhat tm understajd them you need to have other uesic knowledgg. Sm, lvt's say I want to study for some specific reason, the rubject of abstrart algebra.
Cotld this quesdlon be accepved?

What sroule I oearn bdwore abstract slgebra to understabd it
PARATOR ';') AS authors FROM Book b author_book ON ab.book_id b.id LEFT JOIN ab.author_id BY b.id "> column="book_id" name="id" /> column="slug" name="book_slug" /> <field column="title" name="book_title" <field column="isbn" name="book_isbn" /> <field column="publisher" name="book_publisher" /> <field column="release_year" name="book_release_year" /> <field name="book_language" /> <field column="page_count" name="book_page_count" /> <field column="description" name="book_description" /> <field column="print" name="book_print" <field name="book_added_by_id" <field name="book_created" /> <field column="authors" splitBy=";" name="authors" /> </entity> </document> The id field in my schema.xml (which the same as in the default shipped core <field name="id" type="string" indexed="true" required="true" multiValued="false" /> <uniqueKey>id</uniqueKey> Does know I am A: [B@53bd370f not a hash, the result of a byte[].toString(). Whatever Mysql is returning is being treated as a byte[] instead of String. Try id to or like SELECT cast(CONCAT('book_', b.id) AS book_id... Q: Order to learn There are a lot of subjects that to them you to have other basic knowledge. So, say I want to study for some specific the subject of abstract algebra. Could this question be accepted? What should I learn before to understand it
PARATOR ';') AS authors
            FROM Book b
            lEFT JOIN auThor_bOok Ab On aB.booK_id = b.Id
            LEFT JOIN AuthOR a ON A.id = ab.author_id
            GROUP BY b.iD
            ">
        <fielD cOLumn="BOoK_id" naMe="id" />
        <fieLD cOLUmn="SlUg" NamE="bOOk_Slug" />
        <fIelD column="Title" name="bOok_TiTle" />
        <field coluMN="iSbn" name="booK_isBn" />
        <field columN="puBlisheR" nAme="BOok_puBliSher" />
        <fIeld coLUmn="relEase_year" nAmE="Book_reLEase_yeaR" />
        <FIeLd coLumn="language" name="bOOk_LAnguage" />
        <field coLumn="paGe_COuNT" NamE="boOk_page_counT" />
        <fIeld cOLumn="desCRiPTIOn" nAMe="book_descripTion" />
        <field coLUmn="Print" nAmE="boOK_print" />
        <Field CoLUmn="Added_by_id" naMe="boOk_added_by_Id" />
        <fielD Column="cREated" naMe="book_CreAteD" />
        <fieLD cOlUmn="AuTHorS" SpLitbY=";" naMe="authorS" />
    </eNtIty>
</doCumeNT>

tHE id fIelD in mY scheMa.xml (which is tHe sAme aS In tHe defAult sHippEd Core cOllectIon1):
<fiElD name="id" type="striNg" inDexed="true" StoReD="trUe" RequiREd="true" MulTiVAlued="faLse" />
<uniqUEKeY>iD</UNIqUeKey>

Does anyone knoW wHAT I Am missinG?

A:

the [B@53BD370f Is NOt a hash, bUt The ResuLT Of a byTe[].tosTrIng(). WhateVer MysQL iS rEturninG iS being TrEatEd aS a bytE[] InstEad of a string.
TrY castINg the id to varchAR or char like thIS:
 SeleCt Cast(cONcAT('book_', b.id) aS CHAr) aS boOk_id...

 q:

orDer TO learN a subJeCT (sELf-learning)?

There are a LoT of subJects That to understAnd them you NEED to have oTher BAsIC knowledge. So, leT's say i want to stuDY for some SpeciFic reasoN, the subjeCT Of abstraCt aLgeBra.
couLD ThIs question be aCCEpteD?

WHat shouLd I Learn beForE abStrAct AlGebra to unDerstand It
PARATOR ';') AS authors
          FROMBoo k b 
         LEFT JOIN a u thor _book ab ON ab.book_id  = b. id         LEFT JO I NA u tho raONa. i d= ab. aut hor_id           G RO UP BY b.id
         "> 
       <field  co lumn=" bo ok_ i d" na me= "id"/>
      <f ield colu mn = "slug" name="b o o k_ slug " />
        <fie l dc olumn="title"name=" bo o k_ t i tle " / >
       <f ieldc olumn=" i sb n " nam e ="book_isbn"/>
       < fie ld col um n=" p ublish er" n am e ="b ook_publish er"/>
       <fie l d colum n ="relea se_yea r"nam e="b o ok _r ele as e _ye a r"  />        <fi el dcolum n="l a n g u age"  na me=" book_ language" />     <fi eld c olumn ="pa ge _coun t" nam e="bo ok _page_count" /> 
       <fie ldco lum n= "desc r iption " n ame ="book_ descrip t ion "/ >        <field colum n= " p ri nt" name ="book _ pr in t " />
     <fie l d  colu mn=" a dd ed_by_id " name = "b oo k_added _b y_id"/> 
      <f i eldcolumn ="create d" na m e="book_create d " />
       < fi e l dc olum n=" authors" sp litB y =";"  nam e =" aut h ors"/>
  < /e n tity>
</document>
Th e id f ieldin my schema. xml (which i s  the sam e as in the default sh ipped  core coll e ction1): 
<fie ld name= "id" type = " string"ind exe d=" tru e "  s tored="true"r e quir ed ="true"  mu ltiValu ed= "fa lse " / ><uniqueKe y>id</un iq ue Ke y> 

D oes a n yone kno wwha tI a m mis s ing?
A:

t he [ B@ 53 b d37 0f is n o ta hash ,bu t th e r es ult o f ab yte [].toSt ring(). W hat e verMy sq l is re turning is be in g treatedas  abyte[] i nstead o f a String.
Try casting the idtovarch ar o r char li kethis: SE L ECT ca st(CON CAT(' bo ok_ ' ,  b.id ) as  CH AR ) AS book_ i d ... 

 Q: 
Orde r to le arn a subject (sel f -le arning)?

The rearea lo t o f  s u bje ct s  th a t  to understandthem you n ee d  t o have oth e r b as ic know ledge.So, l e t's say  I want t o study f or  som e spe cific reas on, thesubject o f  abst r ac t alg ebr a.
Cou ld  th is qu estion beaccep ted?
Wh at sho uld I  l earn bef ore abstract algebra to  under stand  it 
PARATOR ';')_AS authors
_   _ __ __ FROM Book_b
  _   _  __ LEFT JOIN author_book ab ON ab.book_id = b.id
     __ ___ LEFT JOIN Author a_ON a.id = ab.author_id
 _ _       _GROUP_BY b.id
 _        _ ">
    _  _<field_column="book_id"_name="id" />
  _     <field_column="slug" name="book_slug" />
   _    <field column="title" name="book_title"_/>
     _  <field column="isbn" name="book_isbn"_/>
 _    _ <field column="publisher"_name="book_publisher" />
_  _    <field column="release_year"_name="book_release_year" />
 _     _<field_column="language" name="book_language" />
___ _  _<field_column="page_count" name="book_page_count"_/>
_     __<field column="description" name="book_description" />
   _   _<field_column="print" name="book_print" />
 _    _ <field column="added_by_id" name="book_added_by_id" />
 _ _ _  <field column="created" name="book_created" />
     _  <field column="authors" splitBy=";" name="authors"_/>
   _</entity>
</document>

The id_field_in my schema.xml_(which_is the_same as in the default shipped core_collection1):
<field name="id"_type="string" indexed="true" stored="true" required="true" multiValued="false" />
<uniqueKey>id</uniqueKey>

Does_anyone know what I_am_missing?

A:

the [B@53bd370f is not a hash,_but the result of a byte[].toString()._Whatever Mysql is returning is_being_treated_as a byte[] instead of_a String.
Try casting the id to_varchar or char_like this:
 SELECT cast(CONCAT('book_', b.id) as CHAR)_AS_book_id...

 Q:

Order to learn a subject_(self-learning)?

There_are a lot of subjects that_to_understand_them you need to have_other basic knowledge. So, let's say_I want to study for some specific reason, the_subject of abstract_algebra.
Could this question be accepted?

What_should_I_learn before abstract algebra to understand it