How to list columns of a table in Bigtable? - google-cloud-platform

cbt -instance=INSTANCE ls table lists column families, but I want to list columns themselves.

Column families are explicitly created at the table level, while columns are dynamic and can be completely different per row. So, a general purpose tool to list columns is not necessarily possible.
You can write something for your particular needs using a client library in your language of choice, or parse the output of cbt read or cbt lookup command which lets you read every column in one or more rows.
The Quickstart Using CBT page has examples of using these commands and the output they create.

cbt ls will print all the tables in your current project and instance.
cbt ls <table_name> will list all the column families for that particular table.
Make sure that you have set the project and instance in this case by creating the .cbtrc file. You can find how to set that up here

Related

Power BI Combining Columns and use lookup

I have two reports: first report has a column with sponsor names (name: Sponsor) and the other report also has sponsor names but written differently (name: Companies). Example:
**Sponsor**
Apple
Target
Amazon
IBM
Samsung
**Sponsor (Other)**
Apple Inc
Target LLC
Amazon Marketplace
IBM Computers
Samsung Company
I have appended these two columns so that they are in the same report called Sponsor_All, column names the same as above. What I would like is to create a new column where it would pull in the names from the sponsor column and change the name of the Sponsor (Other) column based on a lookup table so that all of the names are labeled like the sponsor column. Hope thats makes sense.
It looks like what you need is conditional column of some sort.
First thing I would recommend, when you append the two tables, if column names are the same it will append values from both tables into one column, instead of having two columns with different name and a bunch of null values. After that you can either add Conditional Column and hard code the values (so it will be something like: if Sponsor starts with 'Apple' then 'Apple' etc.).
This is not the best approach though, cause you will have to maintain these conditions manually. Better if there's some sort of pattern that you can notice, e.g. in your example I see that to get from Sponsor (other) to Sponsor you just need to extract the first word. If this is the pattern you always have you can use Custom Column and use formula to extract only the first word.
Lastly, if you already have some sort of lookup table you can merge it (after appending together Sponsors and Sponsors(Other) into one column) and use fuzzy lookup option. In all honesty though I never used it and not sure how good it is. If it gives you good enough result you can "clean it up" in next step with custom or conditional column.

How to insert Billing Data from one Table into another Table in BigQuery

I have two tables both billing data from GCP in two different regions. I want to insert one table into the other. Both tables are partitioned by day, and the larger one is being written to by GCP for billing exports, which is why I want to insert the data into the larger table.
I am attempting the following:
Export the smaller table to Google Cloud Storage (GCS) so it can be imported into the other region.
Import the table from GCS into Big Query.
Use Big Query SQL to run INSERT INTO dataset.big_billing_table SELECT * FROM dataset.small_billing_table
However, I am getting a lot of issues as it won't just let me insert (as there are repeated fields in the schema etc). An example of the dataset can be found here https://bigquery.cloud.google.com/table/data-analytics-pocs:public.gcp_billing_export_v1_EXAMPL_E0XD3A_DB33F1
Thanks :)
## Update ##
So the issue was exporting and importing the data with the Avro format and using the auto-detect schema when importing the table back in (Timestamps were getting confused with integer types).
Solution
Export the small table in JSON format to GCS, use GCS to do the regional transfer of the files and then import the JSON file into a Bigquery table and DONT use schema auto detect (e.g specify the schema manually). Then you can use INSERT INTO no problems etc.
I was able to reproduce your case with the example data set you provided. I used dummy tables, generated from the below queries, in order to corroborate the cases:
Table 1: billing_bigquery
SELECT * FROM `data-analytics-pocs.public.gcp_billing_export_v1_EXAMPL_E0XD3A_DB33F1`
where service.description ='BigQuery' limit 1000
Table 2: billing_pubsub
SELECT * FROM `data-analytics-pocs.public.gcp_billing_export_v1_EXAMPL_E0XD3A_DB33F1`
where service.description ='Cloud Pub/Sub' limit 1000
I will propose two methods for performing this task. However, I must point that the target and the source table must have the same columns names, at least the ones you are going to insert.
First, I used INSERT TO method. However, I would like to stress that, according to the documentation, if your table is partitioned you must include the columns names which will be used to insert new rows. Therefore, using the dummy data already shown, it will be as following:
INSERT INTO `billing_bigquery` ( billing_account_id, service, sku, usage_start_time, usage_end_time, project, labels, system_labels, location, export_time, cost, currency, currency_conversion_rate, usage, credits )#invoice, cost_type
SELECT billing_account_id, service, sku, usage_start_time, usage_end_time, project, labels, system_labels, location, export_time, cost, currency, currency_conversion_rate, usage, credits
FROM `billing_pubsub`
Notice that for nested fields I just write down the fields name, for instance: service and not service.description, because they will already be used. Furthermore, I did not select all the columns in the target dataset but all the columns I selected in the target's tables are required to be in the source's table selection as well.
The second method, you can simply use the Query settings button to append the small_billing_table to the big_billing_table. In BigQuery Console, click in More >> Query settings. Then the settings window will appear and you go to Destination table, check Set a destination table for query results, fill the fields: Project name,
Dataset name and Table name -these are the destination table's information-. Subsequently, in
Destination table write preference check Append to table, which according to the documentation:
Append to table — Appends the query results to an existing table
Then you run the following query:
Select * from <project.dataset.source_table>
Then after running it, the source's table data should be appended in the target's table.

How to create a Fact table from multiple different tables in Pentaho

I have been following a tutorial on creating a data warehouse using Pentaho Data Integration/Kettle.
The tutorial is based off of a CSV file but I am practicing with the northwinds database and postgresql I am trying to figure out how to select values from more than one table then output them into a single table.
My ETL process goes like this: I have several stages for each table, values are selected from each table and stored in a stage table for each table in the database, from there I have my dimensions table set up but I am trying to figure out the step between the stages and the dimensions which is where I am trying to select the values to update the dimensions table.
I have several stages set up for each of my tables at this point I am not sure if I should create a separate values table for each table or a single values table. Any help would be greatly appreciated. Thanks
When I try to select values from multiple tables I get an error that says "we detected rows with varying number of fields" It' seems I would need to create separate tables with
In kette, the metadata structure of the data stream cannot change. As such, if row 1 has 3 columns, one integer and two strings, for example, all rows must have the same structure.
If you're combining rows coming from different sources, you must ensure the structure is the same. That error is telling you that some of the incoming streams of data have a different number of fields.

SAS Data Integration - Create a physical table from metadata structure

i need to use a append object after a series of join that have a conditional run... So the join step may be not execute if the condition is not verified and his work physical dataset will not be created.
The problem is that the append step take an error if one o more input physical dataset are not created.
Is there a smart way to create a physical empty table from a metadata structure of the works table of the joins or to use the append with some non-created datasets?
The create table with the list of all field is not a real solution because i've to replicate it per 8 different joins and then replicate the job 10 times...
Thanks to all
Roberto
Thank you for your comments.
What you should do:
Amend your conditional node so that it would on positive condition to create a global macro variable with value of MAX. On negative condition to create the same variable with value of 0.
Replace offending SQL step with "CREATE TABLE" node
In the options for "CREATE TABLE", specify macro variable for "MAXIMUM OUTPUT ROWS (OUTOBS)". See the picture below for example of those options.
So now when your condition is not met, you will always end up with an empty table. When condition is met, the step executes normally.
I must say my version of DI Studio is a bit old. In my version SQL node doens't allow passing macro variables to SQL options, only integers can be typed in. Check if your version allows it because if it does, then you can amend existing SQL step and avoid replacing it with another node.
One more thing, you will get a warning when OUTOBS options is less then the resulting would be dataset.
Let me know if you have any questions.
See the picture for create table options:
At the end i've created another step that extract 0 row from the source table by the condition 1=0 in the where tab. In this way i have a empty table that i can use with a data/set in the post sql of the conditional run if the work table of the join does not exist.
This is not a solution but a valid work around.

SAS Enterprise Miner split Dataset by binary variable

I am using the SAS Enterprise Miner 13.2.
I have a SAS table as a data source. In this table i have a binary variable D_TYP ( "I" and "P" ) and other categorical variables.
I want to split the data by D_TYP so i got two tables. One with all "I" and the other with "P". The problem i don’t know how.
I have been looking in the taskbar and i tried Filter and Data Partition. I can probably use SAS Code to split the Data but i think there is an other way with the taks.
You could use two filter nodes to do the job, with one filtering out I and the another filtering out P. The resulted data set should only consist of one type of the binary variable. In case you are not familiar with the filter node, click on the option Class Variable at properties panel and apply User specified filter. You have to manually select the group by clicking on its corresponding bar.