bigfunctions > find_lower_value
find_lower_value¶
Call or Deploy find_lower_value ?
✅ You can call this find_lower_value bigfunction directly from your Google Cloud Project (no install required).
- This
find_lower_valuefunction is deployed inbigfunctionsGCP project in 39 datasets for all of the 39 BigQuery regions. You need to use the dataset in the same region as your datasets (otherwise you may have a function not found error). - Function is public, so it can be called by anyone. Just copy / paste examples below in your BigQuery console. It just works!
- You may prefer to deploy the BigFunction in your own project if you want to build and manage your own catalog of functions. This is particularly useful if you want to create private functions (for example calling your internal APIs). Discover the framework
Public BigFunctions Datasets:
| Region | Dataset |
|---|---|
eu |
bigfunctions.eu |
us |
bigfunctions.us |
europe-west1 |
bigfunctions.europe_west1 |
asia-east1 |
bigfunctions.asia_east1 |
| ... | ... |
Description¶
Signature
find_lower_value(arr, x)
Description
Return the offset (zero-based index) of the first value in arr where value <= x
(or null if no value is lower than x).
Examples¶
1. When a strictly lower value exists in array
select bigfunctions.eu.find_lower_value([5, 4, 3, 100], 3.5)
select bigfunctions.us.find_lower_value([5, 4, 3, 100], 3.5)
select bigfunctions.europe_west1.find_lower_value([5, 4, 3, 100], 3.5)
+--------+
| offset |
+--------+
| 2 |
+--------+
2. When an identical value exists in array
select bigfunctions.eu.find_lower_value([5, 4, 3, 100], 4)
select bigfunctions.us.find_lower_value([5, 4, 3, 100], 4)
select bigfunctions.europe_west1.find_lower_value([5, 4, 3, 100], 4)
+--------+
| offset |
+--------+
| 1 |
+--------+
3. When a lower value does NOT exist in array
select bigfunctions.eu.find_lower_value([5, 4, 3, 100], 2)
select bigfunctions.us.find_lower_value([5, 4, 3, 100], 2)
select bigfunctions.europe_west1.find_lower_value([5, 4, 3, 100], 2)
+--------+
| offset |
+--------+
| null |
+--------+
Need help using find_lower_value?
The community can help! Engage the conversation on Slack
For professional suppport, don't hesitate to chat with us.
Found a bug using find_lower_value?
If the function does not work as expected, please
- report a bug so that it can be improved.
- or open the discussion with the community on Slack.
For professional suppport, don't hesitate to chat with us.
Use cases¶
Imagine you have a table of product prices and you want to find the index of the first product in a given list that is priced at or below a certain threshold.
Scenario: You're building a price comparison tool. You have a table with competitor prices for a specific product:
| Competitor | Price |
|---|---|
| A | 12.99 |
| B | 10.50 |
| C | 15.00 |
| D | 9.99 |
| E | 11.75 |
A user sets a maximum price they are willing to pay, say $11.00. You want to quickly find the first competitor in the list offering a price at or below $11.00.
BigQuery SQL using find_lower_value:
SELECT find_lower_value([12.99, 10.50, 15.00, 9.99, 11.75], 11.00) AS first_affordable_competitor_index;
This query would return 1, which is the index of competitor B (remember, it's zero-based indexing).
Other Use Cases:
- Inventory Management: Finding the index of the first bin in a warehouse with stock at or below a reorder point.
- Data Analysis: Quickly locating the first data point in a time series that falls below a certain threshold (e.g., first day temperature dropped below freezing).
- Game Development: Determining the first item in a sorted list of player scores that is less than or equal to a given score.
- Algorithm Optimization: As part of more complex algorithms like binary search variations, where you need to efficiently find the position of an element or the first element meeting a specific condition within a sorted or partially sorted array.
This function provides a concise and efficient way to perform this type of search within BigQuery without needing to write more complex procedural code.
Spread the word¶
BigFunctions is fully open-source. Help make it a success by spreading the word!