Using BigQuery In Command Line

Examine a table

BigQuery offers a number of sample tables that you can run queries against. In this lab, you’ll run queries against the shakespeare table, which contains an entry for every word in every play.

To examine the schema of the Shakespeare table in the samples dataset, run:

bq show bigquery-public-data:samples.shakespeare

In this command you’re doing the following:

bq to invoke the BigQuery command line tool
show is the action
then you’re listing the name of the project:public dataset.table in BigQuery that you want to see.

Run the help command

When you include a command name with the help commands, you get information about that specific command. For example, the following call to bq help retrieves information about the query command.

bq help query

To see a list of all of the commands bq uses, run just bq help.

Run a query

Now you’ll run a query to see how many times the substring “raisin” appears in Shakespeare’s works.

To run a query, run the command bq query "[SQL_STATEMENT]".

Escape any quotation marks inside the [SQL_STATEMENT] with a \ mark, or
Use a different quotation mark type than the surrounding marks (“versus”).

Run the following standard SQL query in Cloud Shell to count the number of times that the substring “raisin” appears in all of Shakespeare’s works:

bq query --use_legacy_sql=false \
'SELECT
   word,
   SUM(word_count) AS count
 FROM
   `bigquery-public-data`.samples.shakespeare
 WHERE
   word LIKE "%raisin%"
 GROUP BY
   word'

In this command:

--use_legacy_sql=false makes standard SQL the default query syntax

Create a new table

Use the bq ls command to list any existing datasets in your project:
```
bq ls
```
You will be brought back to the command line since there aren’t any datasets in your project yet.
Run bq ls and the bigquery-public-data Project ID to list the datasets in that specific project, followed by a colon (:).
```
bq ls bigquery-public-data:
```
Use the bq mk command to create a new dataset named babynames in your project:
```
bq mk babynames
```
Run bq ls to confirm that the dataset now appears as part of your project:
```
bq ls
```

Upload the dataset

Before you can build the table, you need to add the dataset to your project. The custom data file you’ll use contains approximately 7 MB of data about popular baby names, provided by the US Social Security Administration.Run this command to add the baby names zip file to your project, using the URL for the data file:
```
wget http://www.ssa.gov/OACT/babynames/names.zip
```
List the file:
```
ls
```
You can see the name of the file added to your project.
Now unzip the file:
```
unzip names.zip
```
That’s a pretty big list of text files! List the files again:
```
ls
```
The bq load command creates or updates a table and loads data in a single step.

You will use the bq load command to load your source file into a new table called names2010 in the babynames dataset you just created. By default, this runs synchronously, and will take a few seconds to complete.

The bq load arguments you’ll be running are:

datasetID: babynames
tableID: names2010
source: yob2010.txt
schema: name:string,gender:string,count:integer

Create your table:

bq load babynames.names2010 yob2010.txt name:string,gender:string,count:integer

Run bq ls and babynames to confirm that the table now appears in your dataset:
```
bq ls babynames
```
Run bq show and your dataset.table to see the schema:
```
bq show babynames.names2010
```

Run queries

Run the following command to return the top 5 most popular girls names:

bq query "SELECT name,count FROM babynames.names2010 WHERE gender = 'F' ORDER BY count DESC LIMIT 5"

Run the following command to see the top 5 most unusual boys names.

bq query "SELECT name,count FROM babynames.names2010 WHERE gender = 'M' ORDER BY count ASC LIMIT 5"