The “einfo” command is a tool provided by the NCBI’s Entrez Programming Utilities (E-utilities) that allows users to retrieve information about the databases available through the Entrez system. This includes information such as the number of records indexed in each field of a given database, the date of the last update of the database, and the available links from the database to other Entrez databases. When the einfo command is executed, it returns a summary of the database, including its name, description, number of records, and the date of the last update. Additionally, it provides information about the available fields in the database, such as the name, description, and type of each field.
For example, when you execute the command “einfo -d ” it will return a summary of the specified database, including the number of records in the database, the date of the last update, and links to other Entrez databases that can be queried in conjunction with the specified database. Additionally, the einfo command can be used to retrieve information about the links between different Entrez databases. This can be useful for identifying related databases and for constructing complex queries that combine data from multiple databases. It is important to note that the einfo command must be used in conjunction with the other E-utility commands to retrieve and analyze data from Entrez databases. The einfo command is a read-only command and it can be used to retrieve information about the Entrez databases, but cannot be used to perform any action or modification on the database.
einfo Command Examples
1. Print all database names:
# einfo -dbs
2. Print all information of the protein database in XML format:
# einfo -db protein
3. Print all fields of the nuccore database:
# einfo -db nuccore -fields
4. Print all links of the protein database:
# einfo -db protein -links