This topic describes how to use entity expressions to access the properties of a specific sample.
The genomics analysis platform uses genomic entity tables to manage genomic data files. For example, a biological sample (S001) has multiple properties. The value in the FASTQ1 cell is the sample's raw sequence file, which is stored in Object Storage Service (OSS). The tables also use references to link the sample to a patient (NO011121).
The platform provides entity expressions for this purpose. In a template, these expressions allow an application to access the properties of any sample.
$this.attribute.attribute$this refers to the root entity type, such as sample.
Use the . operator to access a property of the entity on the left. If the parsed result is also an entity, you can use the . operator again to access its properties.
Example 1:
In the expression $this.FASTQ1, if the root entity is sample, the application input is the FASTQ1 file for a single sample.
Example 2:
In the expression $this.Samples.FASTQ1, if the root entity is Patient, the application input is a list of the FASTQ1 files for all samples from that patient.