Fsdb::Filter::dbmapreduce - reduce all input rows with the same key

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Group input data by KeyField, then apply a function (the "reducer") to each group. The reduce function can be an external program given by ReduceCommand and ReduceArguments, or an Perl subroutine given in CodeFile or FilterCode. If a "--" appears bef...

Fsdb - a flat-text database for shell scripting

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Fsdb::Filter::dbsort - sort rows based on the the specified columns

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Sort all input rows as specified by the numeric or lexical columns. Dbsort consumes a fixed amount of memory regardless of input size. (It reverts to temporary files on disk if necessary, based on the -M and -T options.) The sort should be stable, bu...

Fsdb::Filter::dbsubprocess - invoke a subprocess as a Fsdb filter object

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Run PROGRAM as a process, with optional ARGUMENTS as program arguments, feeding its standard input and standard output as fsdb streams. A "--" can separate arguments to dbsubprocess from the program and its arguments. As with similar tools, like open...

Fsdb::Filter::dbpipeline - allow db commands to be assembled as pipelines in Perl

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This module makes it easy to create pipelines in Perl using separate processes. (In the past we used to use perl threads.) By default (as with all Fsdb modules), input is from STDIN and output to STDOUT. Two helper functions, fromfile and tofile can ...

Fsdb::Filter::dbfilepivot - pivot a table, converting multiple rows into single wide row

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Pivot a table, converting multiple rows corresponding to the same key into a single wide row. In a normalized database, one might have data with a schema like (id, attribute, value), but sometimes it's more convenient to see the data with a schema li...

Fsdb::Filter::dbmultistats - run dbcolstats over each group of inputs identified by some key

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The input table is grouped by KeyField, then we compute a separate set of column statistics on ValueField for each group with a unique key. Assumptions and requirements are the same as dbmapreduce (this program is just a wrapper around that program):...