I'm stacking on some issue on Tableau when I'm trying to run Custom query with string parameter. I'd like to query one column dynamically from certain table on BigQuery.
My SQL looks like.:
select <Parameters.column for research> as column,
count(*) as N
from table_name
where date=<Parameters.date>
group by 1
Here I'm trying to use parameter as column name.
But unfortunatlly I'm receive string column with one value of the parameter.
Is it possible to execute my request? If it's doable, so how to write the Custom SQL?
Related
I am trying to use Power Query to retrieve a value from SQL Server. I want to parameterize the table name. Like I want to use cell value from one sheet (Sheet1!A1 = Tablename1).
How do I achieve above condition in Power Query?
You may create named range table and refer to it:
= Excel.CurrentWorkbook(){[Name="table"]}[Content]{0}[Column1]
Or use parameter table:
https://www.excelguru.ca/blog/2014/11/26/building-a-parameter-table-for-power-query/
My overall goal is to create new tables by selecting columns in existing tables with certain patterns/tags in their column names. This is in SQL Server.
For example, I have a common need to get all contact information out of a company table, and into its own contact table.
I haven't been able to find a programmatic approach in SQL to express excluding columns from a SELECT statement based on string.
When looking to options like the COL_NAME function, those require an ID arg, which kills that option for me.
Wishing there was something built in that could work like the following:
SELECT *
FROM TABLE
WHERE COL_NAME() LIKE 'FLAG%'
Any ideas? Open to anything! Thanks!!
One trick could be to firstly using the following code to get the column names you desire:
select * from information_schema.columns
where table_name='tbl' and column_name like 'FLAG%'
Then concatenate them into a comma-delimited string and finally create a dynamic sql query using the created string as the column names.
Is it possible in any way (without scripting) to aggregate columns which are stored in a table cell.
Basically what i am trying to achieve here is that if i have the following table
Table 1
KEYNAME | COLUMN_NAME
COUNT_USER | USER_ID
SUM_HOURS | HOURS_WATCHED
Can i do something like
select SUM((select column_name from TABLE1 where KEYNAME = "SUM_HOURS")) FROM MAIN_TABLE
I have the option to script in python via which i know how to achieve this. But i am curious to know if this is possible in any version of SQL or not
Please let me know if the information is insufficient.
No, you cannot use a column name that comes from the result of another query.
You would need to do this in your own code, sending the result to Amazon Redshift as a complete query. (That is, run one query to obtain the column names, then run a second query with those column names inserted.)
I need a Report where a user has to choose 2 parameters. The first parameter contains the years (2017, 2016...), and the second one contains the ID process. Depending on the process that the user chooses, the SQL statement will be one or another. The parameter year is part of the WHERE clause of the SQL contained in the second parameter.
So I have this report with 2 parameters (param_year, Indicador). Query parameter is done using a table datasource, where the IDs column contains the SQL sentences and the Values column contains the text the user must select.
So what I'm doing next is to set ${Indicador} as the SQL statement in the JDBC connection that I have done to the Database. This is reporting me an SQL error
"Failed at query: ${Indicador}.
Any suggestions will be appreciated. Thanks in advance.
Another option is to create multiple datasources in your Master/sub report, then select appropriate datasource using PRD expression on Master/sub Report -> Attributes -> query -> name attribute.
More detailed explanation:
Create a query (I mean a query as a PRD object, which uses the PRD datasource) for every SQL string you need and move the SQL strings from the parameter table into Report Designer queries definitions.
Replace the SQL strings in your parameter table with names of corresponding queries, e.g:
Use the value of your parameter (which should be equal to the PRD query name) as value for Master/sub Report -> Attributes -> query -> name attribute:
You need Pentaho Data Integration to do this kind of dynamic query
If the table structure (output columns) for both queries is the same, you could put them together into one big SQL statement with UNION ALL and put in each query "WHERE ${Indicador} = ValueToRunThisQuery".
The optimizer should be smart enough to know the not-selected subquery is going to return zero rows and not even run it. You can supply a few null columns if one query has fewer columns, but the data types have to be the same for filled columns.
If the output table structure is different between the two queries they should be in different data sources, or even reports.
SELECT ID, BLA, BLA, BLA, ONLY_IN_A
FROM TABLE A
WHERE ${Indicador} = "S010"
UNION ALL
SELECT ID, BLA, BLA, BLA, NULL
FROM TABLE B
WHERE ${Indicador} = "S020"
I have a form where people can type in a start and end date, as well as a column name prefix.
In the backend, I want to do something along the lines of
SELECT *, CAST('{{startDate}}' AS TIMESTAMP) AS ({{prefix}} + '_startDate')
Is this possible? Basically, I want to dynamically create the name of the new column. The table is immediately returned to the user, so I don't want to mutate the underlying table itself. Thanks!
You can execute dynamic query that you have prepared by using EXECUTE keyword, otherwise it is not possible to have dynamic structure of SQL.
Since you are preparing your SQL outside database, you can use something like:
SELECT *, CAST('{{startDate}}' AS TIMESTAMP) AS {{prefix}}_startDate
Assuming that {{prefix}} is replaced with some string by your template before it is sent to database.