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| 1 | +#!/usr/bin/env python |
| 2 | + |
| 3 | +# Copyright 2016 Google Inc. |
| 4 | +# |
| 5 | +# Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | +# you may not use this file except in compliance with the License. |
| 7 | +# You may obtain a copy of the License at |
| 8 | +# |
| 9 | +# http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | +# |
| 11 | +# Unless required by applicable law or agreed to in writing, software |
| 12 | +# distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | +# See the License for the specific language governing permissions and |
| 15 | +# limitations under the License. |
| 16 | + |
| 17 | +"""Command-line app to perform synchronous queries with parameters in BigQuery. |
| 18 | +
|
| 19 | +For more information, see the README.md under /bigquery. |
| 20 | +
|
| 21 | +Example invocation: |
| 22 | + $ python sync_query_params.py --use-named-params 'romeoandjuliet' 100 |
| 23 | + $ python sync_query_params.py --use-positional-params 'romeoandjuliet' 100 |
| 24 | +""" |
| 25 | + |
| 26 | +import argparse |
| 27 | + |
| 28 | +from google.cloud import bigquery |
| 29 | + |
| 30 | + |
| 31 | +def print_results(query_results): |
| 32 | + """Print the query results by requesting a page at a time.""" |
| 33 | + page_token = None |
| 34 | + |
| 35 | + while True: |
| 36 | + rows, total_rows, page_token = query_results.fetch_data( |
| 37 | + max_results=10, |
| 38 | + page_token=page_token) |
| 39 | + |
| 40 | + for row in rows: |
| 41 | + print(row) |
| 42 | + |
| 43 | + if not page_token: |
| 44 | + break |
| 45 | + |
| 46 | + |
| 47 | +def sync_query_positional_params(corpus, min_word_count): |
| 48 | + client = bigquery.Client() |
| 49 | + query_results = client.run_sync_query( |
| 50 | + """SELECT word, word_count |
| 51 | + FROM `bigquery-public-data.samples.shakespeare` |
| 52 | + WHERE corpus = ? |
| 53 | + AND word_count >= ? |
| 54 | + ORDER BY word_count DESC; |
| 55 | + """, |
| 56 | + query_parameters=( |
| 57 | + bigquery.ScalarQueryParameter( |
| 58 | + # Set the name to None to use positional parameters (? symbol |
| 59 | + # in the query). Note that you cannot mix named and positional |
| 60 | + # parameters. |
| 61 | + None, |
| 62 | + 'STRING', |
| 63 | + corpus), |
| 64 | + bigquery.ScalarQueryParameter(None, 'INT64', min_word_count))) |
| 65 | + |
| 66 | + # Only standard SQL syntax supports parameters in queries. |
| 67 | + # See: https://cloud.google.com/bigquery/sql-reference/ |
| 68 | + query_results.use_legacy_sql = False |
| 69 | + query_results.run() |
| 70 | + print_results(query_results) |
| 71 | + |
| 72 | + |
| 73 | +def sync_query_named_params(corpus, min_word_count): |
| 74 | + client = bigquery.Client() |
| 75 | + query_results = client.run_sync_query( |
| 76 | + """SELECT word, word_count |
| 77 | + FROM `bigquery-public-data.samples.shakespeare` |
| 78 | + WHERE corpus = @corpus |
| 79 | + AND word_count >= @min_word_count |
| 80 | + ORDER BY word_count DESC; |
| 81 | + """, |
| 82 | + query_parameters=( |
| 83 | + bigquery.ScalarQueryParameter('corpus', 'STRING', corpus), |
| 84 | + bigquery.ScalarQueryParameter( |
| 85 | + 'min_word_count', |
| 86 | + 'INT64', |
| 87 | + min_word_count))) |
| 88 | + query_results.use_legacy_sql = False |
| 89 | + query_results.run() |
| 90 | + print_results(query_results) |
| 91 | + |
| 92 | + |
| 93 | +if __name__ == '__main__': |
| 94 | + parser = argparse.ArgumentParser( |
| 95 | + description=__doc__, |
| 96 | + formatter_class=argparse.RawDescriptionHelpFormatter) |
| 97 | + parser.add_argument( |
| 98 | + 'corpus', |
| 99 | + help='Corpus to search from Shakespeare dataset.') |
| 100 | + parser.add_argument( |
| 101 | + 'min_word_count', |
| 102 | + help='Minimum count of words to query.', |
| 103 | + type=int) |
| 104 | + |
| 105 | + params_type_parser = parser.add_mutually_exclusive_group(required=False) |
| 106 | + params_type_parser.add_argument( |
| 107 | + '--use-named-params', |
| 108 | + dest='use_named_params', |
| 109 | + action='store_true') |
| 110 | + params_type_parser.add_argument( |
| 111 | + '--use-positional-params', |
| 112 | + dest='use_named_params', |
| 113 | + action='store_false') |
| 114 | + parser.set_defaults(use_named_params=False) |
| 115 | + args = parser.parse_args() |
| 116 | + |
| 117 | + if args.use_named_params: |
| 118 | + sync_query_named_params(args.corpus, args.min_word_count) |
| 119 | + else: |
| 120 | + sync_query_positional_params(args.corpus, args.min_word_count) |
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