Bash script to import data into a partitioned table on BigQuery from another table using a DATE field as a filter.

bq_partition_table.sh

#!/bin/bash
#set -x
oldifs="$IFS"
IFS=$'\n'

echo -n "Type in the project id and press [ENTER]: "
read project_id
echo -n "Type in the dataset name and press [ENTER]: "
read dataset
echo -n "Type in the source table name and press [ENTER]: "
read source_table
echo -n "Type in the destination partitioned table and press [ENTER]: "
read dest_table
echo -n "Type in the DATE column name to be used as partition and press [ENTER]: "
read part_column

declare dates=($(bq query \
    --use_legacy_sql=false \
    --format=csv \
    "SELECT DISTINCT ${part_column} FROM \`${project_id}.${dataset}.${source_table}\`" \
    | tail -n +3))
echo -e "\n"

for partition in ${dates[@]}; do 
    echo "Importing partition date $partition ..."
    bq query --format=none \
             --use_legacy_sql=false \
             --allow_large_results \
             --replace \
             --noflatten_results \
             --destination_table "${dataset}.${dest_table}\$${partition//-/}" \
             "SELECT * FROM \`${project_id}.${dataset}.${source_table}\` WHERE ${part_column}=CAST('${partition}' AS DATE)"
done;

echo "Import finished."

IFS="$oldifs"