Query Mind

  Q.1. How to measure query Xquery performance? Ans :   First, we can analysis our query performance by profiling meter that given on Console page. It’s completely show line by line execution time. Below is the screen-shot of profiling meter: Here, you can see exact what's line is taking more time then you can modify your query as  Second, we use use the  xdmp:query-meters  and  xdmp:query-trace  functions to understand and tune the performance of queries. 

  Q.1.  What is DLS library in MarkLogic? Ans :     DLS library is used for maintain the versions of managed document in the Marklogic server. So that your data will be intact in marklogic while performing any insert/update/delete operation on the document. Marklogic create two copy every time, one is final copy after updating document and second old version copy.    Example: You want to insert data into DB with '/books.xml'. You have inserted data with help of  dls :document-insert-and-manage()  and this function creates two uri: one is  '/books.xml',  and second is '/books_version1.xml'  

  Q.1. What is E-node and D-node in the MarkLogic? Ans:   Evaluator node (e-node) :   E-node that evaluate xquery programs, XCC/XDBC request, and other server request also. E-node also talk with D-node if needs forest data otherwise e-node request evaluated entirely on the e-node. Example-1:   Suppose you run query to do some mathematical calculation and you have no need of forest data, in this case query run entirely on E-Node. Query will not talk with D-node in this case.      Example-2:   Suppose you want extract some forest data, in this case you will run a query on E-node and E-node send a request to D-node for fetching data. D-Node fetch the data and return to E-node.  Data node (D-node):  D-nodes are responsible for maintaining transaction integrity during insert, update and delete operations.  Or we can say D-node is responsible for only data. Example:  if you want to import data without using of E-node, in th...

  Q.1. What is Cluster in Marklogic? Clustering :   A combination of multiple  instances of MarkLogic Server machine called a cluster. Each host in a cluster is sometimes called a node, and each node in the cluster has its own copy of all of the configuration information for the entire cluster.