- Course overview
- Search within this course
- Overview of key IMPC concepts and tools
- Solr query syntax: simplified explanation
- How to use the solr_request function from the impc-api python package
- How to perform a query: q parameter
- Exercise 1: getting familiar with the core
- How to request a limited number of documents: rows parameter
- Exercise 2: requesting three documents
- How to get specific fields: fl parameter
- Exercise 3: selecting specific fields
- Quiz 4: basic Solr parameters
- Filtering data in Solr: narrowing down your results
- How to query a specific field: filter by value
- Exercise 4: filtering by a single field
- How to filter numbers: range search
- Exercise 5: changing the p-value threshold
- How to combine multiple filters: Boolean operators
- Exercise 6: applying multiple filters
- How to exclude data: NOT operator
- Why parentheses are important: combine multiple Boolean operators
- Quiz 5: Boolean operators
- How to handle with null values: exclude empty fields
- Exercise 7: explore null values
- Downloading data: getting large results efficiently
- How to download large dataset effectively: pagination
- How to download the data: batch_solr_request function
- What formats are available for downloading: wt parameter
- Exercise 8: download the data
- What is the difference: JSON vs CSV
- What you need to keep in mind: query responsibly
- Quiz 6: request only necessary data
- Advanced Solr query techniques: faceting and iterating over entities
- Understanding IMPC data: resources and assistance
- Your feedback
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Using simple Solr syntax in your browser
Here is an example of a simple Solr request that you can paste in a browser:
https://www.ebi.ac.uk/mi/impc/solr/statistical-result/select?q=*:*&fl=marker_symbol,effect_size,p_value&rows=3
In this example, we query the statistical-result core and select the first three documents and three fields:
- marker_symbol
- effect_size
- p-value
Figure 3. Solr request in browser.
Let’s break down the example:
- Base URL: The necessary part of the link that allows us to access the database
- Core name: We need to specify the collection of data. Currently, we have five cores available:
experiment,impc_images,statistical-result,genotype-phenotype, andphenodigm. More information about the data in these cores is provided in this section - Command:
selectis the only available command for the IMPC data. It instructs Solr to execute a search query and return documents matching the specified parameters - Solr Parameters: In this example, we have three parameters:
q,fl, androws, separated by ampersands (&)
We will look at the output in the next section.