migrate-fields.sh

#!/usr/bin/env bash
#
# Moves DSpace metadatavalues from one field to another. Assumed to be running
# as the `postgres` Linux user. You MUST perform a full Discovery reindex after
# doing this, ie: index-discovery -bf
#
# Alan Orth, April, 2016

# Exit on first error
set -o errexit

# IDs of fields to move, in this format:
# 
# old_field new_field
#
# fields are separated with tabs or spaces. Uses bash's `mapfile` to read into
# an array.
mapfile -t fields_to_move <<TO_MOVE
66  109 #dc.type
#72  202 #cg.title.journal
#76  203 #cg.subject.ilri
#82  208 #cg.subject.cpwf
#88  210 #cg.subject.ccafs
#106 215 #cg.subject.cifor
#108 217 #cg.subject.iwmi
TO_MOVE

# psql stuff
readonly DATABASE_NAME=dspacetest
readonly PSQL_BIN="/usr/bin/env psql"
# clean startup, and only print results
readonly PSQL_OPTS="--no-psqlrc --tuples-only --dbname $DATABASE_NAME"

migrate_field() {
    local old_id=$1
    local new_id=$2
    local psql_cmd="UPDATE metadatavalue SET metadata_field_id=${new_id} WHERE metadata_field_id=${old_id}"

    $PSQL_BIN $PSQL_OPTS --echo-queries --command "$psql_cmd" \
        && return 0 \
        || return 1
}

main() {
    local row

    for row in "${fields_to_move[@]}"
    do
        # make sure row isn't a comment
        if [[ $row =~ ^[[:space:]]?# ]]; then
            continue
        fi

        # call migrate_field() with format:
        # migrate_field 66 109
        migrate_field $row

        # relax!
        sleep 1
    done
}

main

# vim: set expandtab:ts=4:sw=4:bs=2