|Direct provider||Read||Finbourne||Provided with LUSID|
Note: The LUSID user running the query must have sufficient access control permissions to both use the provider and enumerate target files and folders in Drive. This should automatically be the case if you are the domain owner.
The query returns a table of data assembled from the contents of the file or files in the order they are read.
Drive.Csv has options that enable you to filter or refine a query.
Note: The --file option is mandatory.
An option takes the form --<option>=<value>, for example --file=trade-file.csv. Note no spaces are allowed either side of the = operator.
If an option:
- takes a boolean value, then specifying that option (for example --noHeader) sets it to True; omitting the option specifies False
- takes multiple string values, then specify a comma-separated list, for example --names=My,Column,Names
To see a help screen of available options, their data types, default values, and an explanation for each, run the following query using a suitable tool:
In the following examples, the select * from @x syntax at the end prints the table of data assembled by the query.
Note: For more examples, try the Luminesce Github repo.
Example 1: Extract data from a particular CSV file
Example 2: Extract data from a matching CSV file
In this example, @@today is a scalar variable that must resolve to exactly one column and one row of data.
Example 3: Extract data from multiple CSV files matched using a regular expression
If --file is a folder in Drive, you must specify the --folderFilter option with a regular expression to nominate one or more files to read.
In this example, data is extracted from three files eod-1.csv, eod-2.csv and eod-3.csv, but not from eod-4.csv. The --addFileName option adds an extra column to the table of results showing the source of each record.
In this example, data is extracted from any file with a File_ prefix, 8 digits, an underscore, and then 6 digits, for example File_01072021_123456.csv:
Example 4: Extract data from multiple files stored in a ZIP archive
In this example, daily.zip is stored in the root Drive folder; data is extracted from any file within it that just has alphabetic characters in its file name.
Example 5: Extract data from a CSV file with no header row, instead supplying column names
Note the number of column names specified must match the inbound number of columns.
Example 6: Infer data types of columns from the first 10 rows
In this example, the --skipInvalidRows option is specified to ignore cells that cannot be successfully converted.