NAME¶

stag-db - persistent storage and retrieval for stag data (xml, sxpr, itext)

SYNOPSIS¶

  stag-db -r person -k social_security_no -i ./person-idx myrecords.xml
  stag-db -i ./person-idx -q 999-9999-9999 -q 888-8888-8888

DESCRIPTION¶

Builds a simple file-based database for persistent storage and retrieval of nodes from a stag compatible document. Imagine you have a very large file of data, in a stag compatible format such as XML. You want to index all the elements of type person; each person can be uniquely identified by social_security_no, which is a direct subnode of person The first thing to do is to build an index file, which will be stored in your current directory:

  stag-db -r person -k social_security_no -i ./person-idx myrecords.xml

You can then use the index "person-idx" to retrieve person nodes by their social security number

  stag-db -i ./person-idx -q 999-9999-9999 > some-person.xml

You can export using different stag formats

  stag-db -i ./person-idx -q 999-9999-9999 -w sxpr > some-person.xml

You can retrieve multiple nodes (although these need to be rooted to make a valid file)

  stag-db -i ./person-idx -q 999-9999-9999 -q 888-8888-8888 -top personset

Or you can use a list of IDs from a file (newline delimited)

  stag-db -i ./person-idx -qf my_ss_nmbrs.txt -top personset

ARGUMENTS¶

-i INDEXFILE This file will be used as the persistent index for storage/retrieval -r RELATION-NAME This is the name of the stag node (XML element) that will be stored in the index; for example, with the XML below you may want to use the node name person and the unique key id

  <person_set>
    <person>
      <id>...</id>
    </person>
    <person>
      <id>...</id>
    </person>
    ...
  </person_set>

This flag should only be used when you want to store data -k UNIQUE-KEY This node will be used as the unique/primary key for the data This node should be nested directly below the node that is being stored in the index - if it is more that one below, specify a path This flag should only be used when you want to store data -u UNIQUE-KEY Synonym for -k -p PARSER This can be the name of a stag supported format (xml, sxpr, itext) - XML is assumed by default It can also be a module name - this module is used to parse the input file into a stag stream; see Data::Stag::BaseGenerator for details on writing your own parsers/event generators This flag should only be used when you want to store data -q QUERY-ID Fetches the relation/node with unique key value equal to query-id Multiple arguments can be passed by specifying -q multple times This flag should only be used when you want to query data -top NODE-NAME If this is specified in conjunction with -q or -qf then all the query result nodes will be nested inside a node with this name (ie this provides a root for the resulting document tree) -qf QUERY-FILE This is a file of newline-seperated IDs; this is useful for querying the index in batch -keys This will write a list of all primary keys in the index -w WRITER This format will be used to write the data; can be any stag format (xml, sxpr, itext) - default XML. Can also be a module that catches the incoming stag event stream and does something with it (for example, this could be a module you write yourself that transforms the stag events into HTML)

SEE ALSO¶

Data::Stag For more complex stag to database mapping, see DBIx::DBStag and the scripts stag-storenode selectall_xml