URL: http://www.firstbasesoftware.com/man/man1/dbemit.htm
Last modified: 4 April 1996
Copyright © by FirstBase Software.
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The output file is the database name with a .emit extension. Creation of this output file can be overridden by using the - flag. This option will cause the output of the emit process to go to standard output -- most often the terminal.
Normally, dbemit(1) does not emit formula fields. However, using the -f flag forces formula fields to be emitted along with real fields. These formula emissions are calculated as they are being emitted.
The -b flag will run the FirstBase tool in batch mode, suitable for shell scripts. This mode produces no output on the terminal, thus can also be used when running the process in the background. The -y flag will run the tool at the terminal without pausing to ask the user if existing files can be destroyed and without pausing for the users permission to continue.
The -B flag will enable the fastest throughput of records from the database. If this flag can be used, the dbemit generation is speeded up a great deal by internal record buffering. Note that no index can be used with record buffering, and that record locking is disabled.
Dbemit(1) normally prints most all data as it is stored in the database. However, alpha fields will be quoted if the -q flag is used, and date and dollar fields will be formatted using the -v flag. Note that for alphanumeric data, embedded quotes ('"') and backslashes (\) are escaped using the standard C and UNIX method of preceding the character with a backslash.
Dbemit(1) provides a convenient method of producing a database image file that can be directly downloaded into a different database management system. The 'comma separated field' format is compatible with many other database management packages.
It is also possible to change the field separator used by dbemit. This is done using the -c flag. As an example, the following command will emit data from the database phonelist using the index friends.
dbemit -d phonelist -i friends - -c :
Furthermore, this data will be emitted to standard output, and the field separator will be a colon, not a comma.
As another example, -c \| could be used to change the separator to the vertical bar character ('|'). (Note the escaping of the pipeline character due to the shell.)
By using the -t flag, dbemit(1) will produce output that is ready to be submitted to tbl(1), the table production program that works in conjunction with nroff(1). This means that the following command would produce a formatted report from a database using non-database, standard UNIX tools to do the formatting:
dbemit -d phonelist -t - | tbl | nroff -me -Tlp
Note that the entire phonelist is printed here -- not just an indexed sub-section of the database. A database screen mask can also be applied to the dbemit process (the -s flag) to reorder or ignore particular fields.
It is also possible to upload values into a FirstBase database file. See dbload(1).
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