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einfo

As new Insider's Guide classes are no longer being offered, this site is not currently being updated. Please refer to NCBI's E-utilities documentation for more up-to-date information.

The einfo command uses the EInfo utility to display a list of NCBI databases which can be accessed by E-utilities, or to display summary statistics and information about indexed fields and links in a specific database.

Input

The einfo command has two modes (see below for details).

If the -dbs argument is used, einfo requires no additional input.

If the -db argument is used, einfo requires a single database name.

Output

If the -dbs argument is used, einfo outputs a text list of NCBI databases which can be accessed by E-utilities.

If the -db argument is used, einfo outputs information (in XML format, by default) about the database specified in the -db argument: summary statistics, information about indexed fields, and/or links to other databases. You can control which information is output using the -fields and -links arguments (see below); using either of these options will output information in text instead of XML.

Arguments

The einfo command allows the following arguments:

  • -dbs: Outputs a text list of NCBI databases which can be accessed by E-utilities.
  • -db: Allows you to specify a database name about which you wish to receive information.
    • Example: -db pubmed
  • -fields: Overrides the default XML output and prints a text list of indexed fields for the database specified by the -db parameter.
  • -links: Overrides the default XML output and prints a text list of links (for use with the ELink utility) for the database specified in the -db parameter.

Examples:

Display a text list of databases which can be accessed by E-utilities:

einfo -dbs

Display summary statistics for PubMed and information about PubMed indexed fields and links, in XML format:

einfo -db pubmed

Display a text list of PubMed indexed fields:

einfo -db pubmed -fields

Display a text list of PubMed links:

einfo -db pubmed -links

Display a text list of PubMed indexed fields and links:

einfo -db pubmed -fields -links
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Last Reviewed: July 30, 2021