Bigquery nested json. Nov 20, 2020 · New to bigquery here.

Bigquery nested json Jun 3, 2021 · Sometimes your data lands in BigQuery as a nested JSON string. Jan 23, 2021 · What is Nested Data? BigQuery supports loading and querying nested and recurring data from source formats that support object-based schemas for example JSON. Apr 22, 2025 · What Is JSON in BigQuery? In BigQuery, JSON is a flexible, semi-structured data format that allows for schema-on-read processing. Aug 21, 2016 · I have data in JSON format with nested arrays in them. llc and james@southshore. It’s best to use this strategy when the relationships are hierarchical and frequently queried together, such as in parent-child relationships. Illustration of nested and recurring data – Image by Author The address column contains an array of values. Sep 30, 2024 · When working with JSON data, Newline-Delimited JSON (NDJSON) is the preferred format for loading into BigQuery, but you may often encounter non-NDJSON data (standard JSON format). The Basics of JSON Objects To effectively query JSON objects in BigQuery, it is crucial to understand their structure and properties. Applications can use a "schema-on-read" approach, where the Oct 24, 2025 · This document describes how to create a table with a JSON column, insert JSON data into a BigQuery table, and query JSON data. We will show how to work with the data and explore useful BigQuery functions, including UNNEST. Understanding JSON_QUERY_ARRAY JSON_QUERY_ARRAY is a function in BigQuery SQL that focuses on extracting a JSON array from a JSON string and converts it into a SQL ARRAY<JSON-formatted STRING> or ARRAY<JSON> value. Your example row has many newline characters in the middle of your JSON row, and the parser is trying to interpret each line as a separate JSON row. It excels at analyzing massive Nov 20, 2020 · New to bigquery here. May 9, 2016 · 2 There doesn't seem to be anything problematic with your schema, so BigQuery should be able to load your data with your schema. You can also find us at Jun 10, 2025 · A practical guide to using JSON in BigQuery, with sample code patterns and function references for core foundational use-cases Aug 11, 2025 · Learn how to use JSON data manipulation functions in BigQuery to extract, transform, and query JSON data efficiently with practical examples and tips. For information on handling nested and repeated data in GoogleSQL, see the GoogleSQL migration guide. See full list on holistics. This flexibility is ideal for handling nested or evolving data, making it highly suitable for modern Dec 15, 2020 · I'm trying to load the json data from an API into bigquery table on GCP however I got an issue that the json data seem to miss a square bracket so it got an error Oct 24, 2025 · Working with JSON data in Google SQL This document describes how to create a table with a JSON column, insert JSON data into a BigQuery table, and query JSON data. JSON objects consist of key-value pairs, where each key represents a field or property, and the value can be of any JSON-supported data type. JSON allows for a flexible schema that supports nested value pairs and arrays. One example might be an a column that has one key for each item — with details about the item nested as shown below. In this article, we will show you how to handle nested data in BigQuery. Categories The JSON functions are grouped into the following categories based on their Oct 30, 2018 · If you convert your json data to single line json, you can create the table in bigquery. Describes JSON data types and options, and limitations of loading JSON files from Cloud Storage. The above query works to explode multiple arrays. I am currently able to extract keys with the aid of 1 and 2, but parsing the value of JSON object is producing unexpected results. JSON string column with BigQuery JSON functions Pros: Easiest to use directly from the source system Flexible schema as Oct 24, 2025 · Using nested and repeated fields BigQuery doesn't require a completely flat denormalization. GoogleSQL for BigQuery supports the following functions, which can retrieve and transform JSON data. JSON is a widely used format that allows for semi-structured data, because it does not require a schema. cloud. If you are working on automating this say using Python, then you would need to use python libraries (google. There is a search index defined on the logrec json column which would be nice to use. BigQuery natively supports JSON data using the JSON data type. Applications can use a "schema-on-read" approach, where the application ingests the data and then May 2, 2024 · By integrating BigQuery’s UDF capabilities with dbt’s powerful macro and model management, we’ve developed a flexible, dynamic solution to handle nested JSON data with ease. Oct 24, 2025 · The preferred query syntax for BigQuery is GoogleSQL. Querying nested data uses "dot" syntax to reference leaf fields, which is similar to the syntax using a join. For further guidance, or if you have specific challenges with your JSON data transformations, feel free to reach out to us at nick@southshore. We will explore a common example of event-data exported from Firebase and loaded into BigQuery. Learn manual and automated methods in this article. Nov 19, 2022 · BigQuery out of the box provides option to download the data in JSON format and that would result in the format as mentioned in the problem statement. Attempt: I tried the below query but it did not give the expected response: May 9, 2020 · A common way of logging and delivering data from production systems is via the JSON format. Dec 9, 2020 · Furthermore, BigQuery makes it really easy to ingest JSON, XML, and other such data into its tables, to facilitate further analysis. Categories The JSON functions are grouped into the following categories based on their behavior: Oct 30, 2025 · BigQuery supports loading nested and repeated data from source formats that support object-based schemas, such as JSON files, Avro files, Firestore export files, and Datastore export files. May 10, 2023 · I would like to extract nested JSON with dynamic keys. Dec 20, 2022 · Earlier in 2022 BigQuery introduced native support for the JSON datatype. Shows how to load nested/repeated JSON data and hive-partitioned JSON data. Nov 8, 2023 · 0 How can I use bigquery search () on a nested json using a wildcard in my string literal? Example below, note the % wildcard at the end of the search string. Unlike the fixed schema required by STRUCT types, JSON doesn’t impose a predefined structure, enabling applications to ingest and query data based on assumptions. Oct 30, 2025 · BigQuery supports loading nested and repeated data from source formats that support object-based schemas, such as JSON files, Avro files, Firestore export files, and Datastore export files. Nesting data (STRUCT) Nesting data lets you represent foreign entities inline. Aug 9, 2017 · BigQuery query nested json Asked 7 years, 9 months ago Modified 4 years, 6 months ago Viewed 6k times Jun 17, 2023 · I would like to extract the JSON data from the json_data table and insert it into the users table with the appropriate structure. This is especially useful when representing customers, orders, and delivery details in a single, unified format for querying and reporting. This lab is an in-depth walkthrough of working with semi-structured data (ingesting JSON, Array data types) inside of BigQuery. @ZiyaMertKarakas fyi, the link has example nested structure - there id, firstname, lastname, dob into separate table and address goes in separate table This article aims to demystify JSON_QUERY_ARRAY, detailing its syntax, usage, and practical applications within the BigQuery console. Flatten nested JSON string to different columns in Google BigQuery Asked 6 years, 7 months ago Modified 2 years, 4 months ago Viewed 9k times Oct 24, 2025 · Using nested and repeated fields BigQuery doesn't require a completely flat denormalization. I've been following the documentation on how to create an empty schema and do a bq load job on my json data and working through each error . Jan 23, 2025 · Querying and Filtering Nested and Repeated Fields in BigQuery BigQuery is Google’s serverless, highly scalable, and cost-effective data warehousing service. The preferred query syntax for BigQuery is GoogleSQL. For many legacy SQL queries, BigQuery can automatically flatten the data. BigQuery supports loading and exporting nested and repeated data in the form of JSON and Avro files. Oct 24, 2025 · This document details how to query nested and repeated data in legacy SQL query syntax. io Feb 11, 2025 · The recommended way to denormalize data in BigQuery is to use nested and repeated fields. This new development opens the door to a lot of interesting use cases, given the widespread adoption a May 26, 2023 · Here are some common difficulties you might encounter: Data Structure: JSON data can have complex, deeply nested structures, making it challenging to extract and manipulate specific information. Data Integrity: JSON data can be prone to inconsistencies or missing values, especially when obtained from multiple sources or generated dynamically. You can use nested and repeated fields to maintain relationships. Previously, one would have had to store the JSON data in a string column. Aug 8, 2025 · Nested JSON structures are beneficial when working with complex data that naturally lends itself to a hierarchical structure. First, make sure you are uploading newline-delimited JSON to BigQuery. This format Jul 10, 2024 · The combination of dbt and BigQuery is a powerful toolkit for handling JSON data. Aug 17, 2023 · Venkatesh, to elaborate further do you mean, how to 1) identify number of nested objects 2) normalize it (unnest) 3) load in table each per normalized structure. Denormalizing your schema into a single table with nested and repeated fields can yield performance improvements, but the SQL syntax for working with array data can be tricky. By following this guide, you can transform even the most nested JSON structures into a well-organized database schema. GoogleSQL for BigQuery supports the following functions, which can retrieve and transform JSON data. Here's an example: "data": {"events": [[1, 1271, 518, 945], [1, 1287, 495, 963], the length of the sub-arrays can be 3 or 4, and the first Sep 24, 2024 · I recently had a BigQuery puzzle involving JSON data files and being able to query their content where the field names of the JSON objects… This page provides an overview of the query syntax for using standard SQL in BigQuery on Google Cloud. Aug 30, 2024 · Discover efficient ways to export JSON data to BigQuery for advanced analysis and integration with diverse technologies. JSON objects can also contain nested objects, allowing you to represent complex data structures in a hierarchical manner How are nested data structures used in BigQuery? Yet if done well, nested data structure (JSON) is a very powerful mechanism to better express hierarchical relationships between entities comparing to the conventional flat structure of tables. Jan 9, 2025 · This post will guide you through the process of parsing complex, nested JSON and transforming it into structured, queryable data within BigQuery’s nested columns. &quot;[object To read data from a JSON field in Bigquery you will need to use the UNNEST Command. llc. bigquery) and call the SQL, then use Pandas dataframe to store the output. Aug 19, 2018 · Shows how to load JSON files from Cloud Storage into a new table, or append to, or overwrite a table. The different addresses in the array are the recurring data. In BigQuery we have a few options to consider when choosing how to store this data for use in BigQuery. For example, If you have a table in Bigquery which has JSON data like below. riv aa8 sl2nw 9jmjv9v jc i9ed 4xtiaw esz f8gbuo v6n