nosql - MarkLogic:在单个事务中提交多个语句

Question

我想对文档进行版本控制，为此我们遵循以下方法在单个事务中 checkout 和 checkin 文档。

(:--------------------------- XQuery Starts ---------------------------:)
xquery version "1.0-ml";
declare namespace html = "http://www.w3.org/1999/xhtml";
import module namespace dls = "http://marklogic.com/xdmp/dls" at "/MarkLogic/dls.xqy";

declare function local:ManageDocument($docUri)
{
    let $query := fn:concat('
      xquery version "1.0-ml";
      declare namespace html = "http://www.w3.org/1999/xhtml";
      import module namespace dls = "http://marklogic.com/xdmp/dls" at "/MarkLogic/dls.xqy";
      declare variable $docUri as xs:string external;
      dls:document-manage($docUri,fn:false(),fn:concat("First Version of ", $docUri))'
    )

    return xdmp:eval(
      $query,
      (xs:QName("docUri"), $docUri),
      <options xmlns="xdmp:eval">
        <prevent-deadlocks>true</prevent-deadlocks>
      </options>
    )
};

let $docUri := "/searchable/as-2018-1981_standard.pdf.xml"
let $isManaged  := dls:document-is-managed($docUri)
let $manageDoc := if($isManaged) then() else local:ManageDocument($docUri)

let $chechoutStatus := dls:document-checkout-status($docUri)
let $checkOut   := if($chechoutStatus and $isManaged) then (fn:error(xs:QName('Error'), "Already Editing")) else dls:document-checkout-update-checkin($docUri, element {"ROOT"} {"HELLO WORLD!"}, "document-checkout-update-checkin", fn:true())

return $manageDoc
(:--------------------------- XQuery Ends ---------------------------:)

但是，它抛出以下异常:

[1.0-ml] XDMP-PREVENTDEADLOCKS: xdmp:eval("
 xquery version "1.0-
ml";
 declare ...", (fn:QName("","docUri"), "/searchable
/as-2018-1981_standard.pdf.xml"), <options xmlns="xdmp:eval"><prevent-
deadlocks>true</prevent-deadlocks></options>) -- Processing an update from an
update with different-transaction isolation could deadlock

为了克服这个问题，我修改了 XQuery 来解决我们的目的:

(:--------------------------- New XQuery Starts ---------------------------:)
xquery version "1.0-ml";
declare namespace html = "http://www.w3.org/1999/xhtml";
import module namespace dls = "http://marklogic.com/xdmp/dls" at "/MarkLogic/dls.xqy";

declare function local:ManageDocument($docUri)
{
    let $query := fn:concat('
      xquery version "1.0-ml";
      declare namespace html = "http://www.w3.org/1999/xhtml";
      import module namespace dls = "http://marklogic.com/xdmp/dls" at "/MarkLogic/dls.xqy";
      declare variable $docUri as xs:string external;
      dls:document-manage($docUri,fn:false(),fn:concat("First Version of ", $docUri))'
    )

    return xdmp:eval(
      $query,
      (xs:QName("docUri"), $docUri),
      <options xmlns="xdmp:eval">
        <prevent-deadlocks>true</prevent-deadlocks>
      </options>
    )
};

declare function local:CheckouotDocument($docUri)
{
  let $query := fn:concat('
    xquery version "1.0-ml";
    declare namespace html = "http://www.w3.org/1999/xhtml";
    import module namespace dls = "http://marklogic.com/xdmp/dls" at "/MarkLogic/dls.xqy";
    declare variable $docUri as xs:string external;
    (: dls:document-checkout($docUri, fn:true(), "updating doc", 3600) :)
    dls:document-checkout-update-checkin($docUri, element {"ROOT"} {"HELLO WORLD!"}, "document-checkout-update-checkin", fn:true())
   ')

   return xdmp:eval(
      $query,
      (xs:QName("docUri"), $docUri),
      <options xmlns="xdmp:eval">
        <prevent-deadlocks>true</prevent-deadlocks>
      </options>
    )
};

let $docUri := "/searchable/as-2018-1981_standard.pdf.xml"
let $isManaged  := dls:document-is-managed($docUri)
let $manageDoc := if($isManaged) then() else local:ManageDocument($docUri)

let $chechoutStatus := dls:document-checkout-status($docUri)
let $checkOut   := if($chechoutStatus and $isManaged) then (fn:error(xs:QName('Error'), "Already Editing")) else local:CheckouotDocument($docUri)

return $manageDoc
(:--------------------------- New XQuery Ends ---------------------------:)

上面的 XQuery 正在按预期工作，但是，如果有人能帮助我以更高效和简化的方式解决我的目的，那就太好了。

Answer 1

您可以使用 xdmp:invoke-function() 稍微简化您的代码而不是为 xdmp:eval() 构造字符串，并通过声明变量避免重复选项:

xquery version "1.0-ml";
declare namespace html = "http://www.w3.org/1999/xhtml";
import module namespace dls = "http://marklogic.com/xdmp/dls" at "/MarkLogic/dls.xqy";

declare variable $OPTIONS := 
  <options xmlns="xdmp:eval">
    <prevent-deadlocks>true</prevent-deadlocks>
  </options>;

declare function local:ManageDocument($docUri)
{
  xdmp:invoke-function(function() {
    dls:document-manage($docUri, fn:false(), "First Version of "||$docUri)
  }, $OPTIONS)
};

declare function local:CheckouotDocument($docUri)
{
  xdmp:invoke-function(function() {
    (: dls:document-checkout($docUri, fn:true(), "updating doc", 3600) :)
    dls:document-checkout-update-checkin($docUri, element {"ROOT"} {"HELLO WORLD!"}, "document-checkout-update-checkin", fn:true())
  }, $OPTIONS)
};

let $docUri := "/searchable/as-2018-1981_standard.pdf.xml"
let $isManaged  := dls:document-is-managed($docUri)
let $manageDoc := if ($isManaged) then() else local:ManageDocument($docUri)

let $chechoutStatus := dls:document-checkout-status($docUri)
let $checkOut   := if ($chechoutStatus and $isManaged) then (fn:error(xs:QName('Error'), "Already Editing")) else local:CheckouotDocument($docUri)

return $manageDoc