Athena query json array 19 287. To obtain the size of a JSON-encoded array or object, use the json_size function, and specify the column containing the JSON string and the JSONPath expression to the array or object. Jul 30, 2021 · I want to parse the JSON column in Athena but I have a problem in one column. Many applications and tools output data that is JSON-encoded. It supports a bunch of big data formats like JSON, CSV, Parquet, ION, etc. The following table shows the data types supported in Athena. those values can be Apr 1, 2023 · I am currently having table with one column name event (string) in athena external table and i just want to get that value as a JSON. {test. The following query creates an array words, and selects the first element hello from it as the first_word, the second element amazon (counting from the end of the array) as the middle_word, and the third element athena, as the last_word. Jun 16, 2022 · I have a table in Athena where one of the columns is of type array. temp DTempK, list[1]. Glue-crawler recognises this Nov 19, 2021 · I have a nested json data structure like below, end goal was to show the data in Quicksight from Athena. 172 Presto Release Documentation. Assuming that structure array<struct<expand:string,id:string,name:string>> corresponds to column members, you would need to do May 28, 2024 · I had previously had asked a question, and it was answered (AWS Athena Parse array of JSON objects to rows), about parsing JSON arrays using Athena but running into a variation. Because the data is structured - this use case is simpler. SELECT data FROM mytable CROSS JOIN UNNEST(CAST(json_parse(data) AS ARRAY<json>)) The array has two json entries and I get two rows now, but each row contains all two jsons instead of one each Jul 8, 2020 · Complex types in data If you are using Athena to query JSON data you have most likely already worked with complex types in your data in the form of an array property or an object property. Athena supports all of the native Presto data types. Nov 15, 2018 · I got the following format of JSON document with nested structures { "id": "p-1234-2132321-213213213-12312", "name": "athena to the Feb 16, 2017 · In this post, you’ve seen how to use Amazon Athena in real-world use cases to query the JSON used in AWS service logs. Amazon Athena enables you to analyze a wide variety of data. Also refer to this talks about the requirement To parse JSON-encoded data in Athena, make sure that each JSON document is on its own line, separated by a new line. This has been asked a few times and I don't think someone made it work with a array of json: aws athena - Create table by an array of json object AWS Glue Custom Classifiers Json Path Mar 24, 2025 · Your source data often contains arrays with complex data types and nested structures. To learn the basics of querying JSON data in Athena, consider the following sample planet data: Overview This Article shows how to import a nested json like order and order details in to a flat table using AWS Athena . Apr 13, 2017 · I have a table in Athena where one of the columns is of type array<string>. If you want the table to have three columns for name, age and salary you'll need to declare those columns in your table DDL To determine if a specific value exists inside a JSON-encoded array, use the json_array_contains function. I am using below query but it converts it into string: select C JavaScript Object Notation (JSON) is a common method for encoding data structures as text. However, when I run select * from mytable where array_contains(myarr,'foobar') limit 10 it seems Athena doesn't have the array_contains function: SYNTAX_ERROR: line 2:7: Function array_contains not registered Is there an alternative way to check if the array contains a particular string? Mar 3, 2018 · 0 Gave a response to a similar question: I used a simple approach to get around the struct -> json Athena limitation. When I select from the Athena then the result format like this. One of the columns crawled as string, contains json : May 18, 2023 · How we coerced Athena into constructing and exporting tables as rows of JSON objects Jan 24, 2023 · I have a json formatted like: myjson = {"key":["value1","value2"]} and a I want to convert it as string Sometime this json can return null: myjson = {"key":n View query stats Work with views Use saved queries Use parameterized queries Use the cost-based optimizer Query S3 Express One Zone Query Amazon Glacier Handle schema updates Query arrays Query geospatial data Query JSON data Use ML with Athena Query with UDFs Query across regions Query the AWS Glue Data Catalog Query AWS service logs Query web I'm querying a JSON file from S3 to get the first element values for an array: SELECT list[1]. So you need to cast to array and use unnest (removed trailing commas from json): -- sample data WITH dataset (json_str) AS ( values ('[{ "data": [{ For information about using SQL that is specific to Athena, see Considerations and limitations for SQL queries in Amazon Athena and Run SQL queries in Amazon Athena. This includes tabular data in CSV or Apache Parquet files, data […] How to translate a nested, JSON-formatted data structure into a tabular view by using Amazon Athena, and then visualize the data in Amazon QuickSight. The data contains unnamed JSON key:value pairs. To get started with Athena you define your Glue table in the Athena UI and start writing SQL queries. Querying complex JSON objects in AWS Athena AWS Athena is a managed big data query system based on S3 and Presto. I want to reach to Message. How do I perform a wildcard search in this column? Expe Jul 28, 2022 · 1 json_extract_scalar will not help here because it returns only one value. Aug 16, 2021 · I have one S3 bucket with some data stored. I would like to add all of them to the Athena Table with the filtered values. Jan 18, 2019 · April 2024: This post was reviewed for accuracy. 0, InnerKey2:"someString" }", OuterKey3:1625833855741 } This structure looks like json, but its not exactly json as the key doesn't have quotes I used Glue-crawler to create table from S3 folder. To determine if a specific value exists inside a JSON-encoded array, use the json_array_contains function. id = 2657789; This returns following output: DateTime DTempK DTempKmin DTempKmax IdF 1 1563030000 290. JSON In my experience, most JSON data isn’t very Hi, The environment is, there are multiple JSON files in a S3 bucket. Amazon Athena lets you query JSON-encoded data, extract data from nested JSON, search for values, and find length and size of JSON arrays. May 16, 2024 · Working with AWS Athena and trying to parse data found in a column with a defined data type of array so that each JSON object in the array is broke out into a separate row. Jun 13, 2020 · Query CSV Files Download the attached CSV Files. For more information about UNNEST , see Flattening Nested Arrays . "owm_forecast_data" where city. Examples in this section show how to change element's data type, locate elements within arrays, and find keywords using Athena queries. Create the Folder in which you save the Files and upload both CSV Files. Trino improved vastly json path support but Athena has much more older version of the Presto engine which does not support it. To define a dataset for an array of values that includes a nested BOOLEAN value, issue this query: Jun 2, 2020 · The reason why the JSON format that you are using was not working is because of this. Athena is the most powerful tool that can scan millions of nested documents on S3 and transform it to flat structure if needed. Within the query itself I want convert the output into the format below: Athena Best Practices recommends to have one json per row: Make sure that each JSON-encoded record is represented on a separate line. You can see below s Athena engine version 3 introduces performance, reliability enhancements, new features, and query syntax changes for improved data processing and analytics capabilities. 329 290. I want to do query on those data using Athena tables. In Amazon Athena, you can create tables from external data and include the JSON-encoded data in them. temp_max DTempKmax, city. For DML queries like SELECT, CTAS, and INSERT INTO, Athena uses Trino data type names. To flatten a nested array's elements into a single array of values, use the flatten function. main. May 23, 2017 · I want to get result value format JSON from Athena in AWS. Jun 2, 2020 · I have received a data set from a client that is loaded in AWS S3. Some of these use cases can be operational like bounce and complaint handling. All values in the arrays must be of the same type. Athena provides powerful functions to directly build JSON structures from your query results. I don't know if this problem. "field_1" would work for a row column - however, it looks like it's not possible to cast a json to a row in Athena (which is based on Presto 0. For such types of source data, use Athena together with JSON SerDe libraries. The structur Athena engine version 3 introduces performance, reliability enhancements, new features, and query syntax changes for improved data processing and analytics capabilities. May 7, 2022 · Version of Presto currently used by Athena does not support any_match so you will need to use cardinality + filter combination (and it does not support filtering via json path): Apr 26, 2022 · I'm using the array_agg function to merge states into an array. For an example of creating a database, creating a table, and running a SELECT query on the table in Athena, see Get started. value= {report_1=test, report_2=normal, report_3=hard}} Is there an. 172) - see Cast from JSON in the 0. Large arrays often contain nested structures, and you need to be able to filter, or search, for values within them. temp_min DTempKmin, list[1]. To learn the basics of querying JSON data in Athena, consider the following sample planet data: Mar 25, 2021 · If you create an Athena table based on the Json SerDe and you want a single s3 object to contain multiple rows/records inside of it, the expectation is that each row/record is on its own line in the file, and there there is no outer JSON array wrapping all of the records. The behaviour is expected and for your JSON file to work properly each record has to be present on separate line. May 23, 2020 · This query got me closer. Although structured data remains the backbone for many data platforms, increasingly unstructured or semi-structured data is used to enrich existing information or create new insights. The Table is for the Ingestion Level (MRR) and should be named – YouTubeVideosShorten. However, I am having problems to query the nested JSON values. I created a second table where the json columns were saved as raw strings. In Athena I've a column with an array (json), is there a way to calculate the length of that array for every row? Sep 22, 2022 · Unnesting a series of nested JSON objects from a JSON array in Athena 0 Hello, I am currently using Service Now table dumps exported as JSON array files to S3. I used the ChatGPT for the Athena query to creat In order to query fields of elements within an array, you would need to UNNEST it first. Athena engine version 3 introduces performance, reliability enhancements, new features, and query syntax changes for improved data processing and analytics capabilities. Using presto json and array functions I was able to query the data and return the valid json string to my program: Learn how to concatenate strings and arrays in Athena queries. The column includes an escape character. dt DateTime, list[1]. Schemas are applied at query time via AWS Glue. Feb 3, 2024 · This article is a step by step guide for accessing all the JSON files stored in AWS S3 to Athena. Amazon Athena lets you query JSON-encoded data, extract data from nested JSON, search for values, and find length and size of JSON arrays. After researching I found out Quicksight cannot show/handle "ARRAY" datatype for v Oct 22, 2020 · The syntax "fields". The S3 folder path structure is similar to the following: aws s3 ls s3://bucket/data/ PRE data1-2022-09-22/ PRE data2-2022-09-22/ PRE data3-2022-09-22/ Continue to help good content that is interesting, well-researched, and useful, rise to the top! To gain full voting privileges, Learn about using aggregation functions with arrays in Athena. Using the example: Athena engine version 3 introduces performance, reliability enhancements, new features, and query syntax changes for improved data processing and analytics capabilities. Structure of S3 file: { OuterKey1:"OuterValue1", OuterKey2:"{ InnerKey1:4. Jun 17, 2020 · AWS Athena how to work with JSON Author: Ariel Yosef How to query a nested json in AWS Athena Json can contain nested values. You may have source data containing JSON-encoded strings that you do not necessarily want to deserialize into a table in Athena. Jul 3, 2020 · In data formats like JSON it’s very common to have arrays and map properties, and one question that often comes up is how you flatten these structures to work better in a traditional tabular format – in other words, how to turn array elements into rows. This isn't my area of expertise, so I was looking for a little help. The following query lists the names of the users who are participating in "project2". 19 2657789 Now November 16, 2025 Athena › ug Query JSON data Athena enables querying JSON data, extracting nested JSON, searching arrays, getting array lengths/sizes, creating tables, and troubleshooting queries. id IdF FROM "og-owm-staging". Follow the instructions from the first Post and create a table in Athena After creating your table – make sure You see your Sep 17, 2025 · data-source , quick-sight , calculations , how-to 5 1535 May 11, 2023 Quicksight is not able to parse json file which contains arrays like I want to upload a data file which has a different data in one section so I want to format it as array but Quicksight is not able to parse that Q&A feature-request , quick-sight , data-preparation 1 839 To facilitate interoperability with other query engines, Athena uses Apache Hive data type names for DDL statements like CREATE TABLE. The answer is the UNNEST operator. Athena engine version 3 Athena engine version 3 introduces performance, reliability enhancements, new features, and query syntax changes for improved data processing and analytics capabilities. In this case, you can still run SQL operations on this data, using the JSON functions available in Presto. To create maps, use the MAP operator and pass it two arrays: the first is the column (key) names, and the second is values. If any of the map value array elements need to be of different types, you can convert them later. Amazon Athena lets you create arrays, concatenate them, convert them to different data types, and then filter, flatten, and sort them. You may convert it to a map<varchar,varchar> and then access it via Subscript Operator: [] Example: To filter an array that includes a nested structure by one of its child elements, issue a query with an UNNEST operator. Jan 22, 2018 · 5 I have nested JSON files on S3 and am trying to query them with Athena. when I run this query: Maps are key-value pairs that consist of data types available in Athena. This query returns a row for each element in the array. Athena will automatically scale up the required CPU to process it without any human intervention. You can leverage json_build_object to create JSON objects and json_build_array for JSON arrays, mapping your relational data into hierarchical JSON formats. I tried the below query to get output containing earth but doesn't work. My JSON file looks like this: To convert data in arrays to supported data types, use the CAST operator, as CAST (value AS type) . Being able to describe most JSON data in table form is one of the most powerful features of Athena. Sep 20, 2022 · I am crawling data from Google Big Query and staging them into Athena. ftqfiqf vynan mnqbnsf svbckmij hgpalw oopkehej cixtcl ynh qcbvu oleqp illwycyf fbsest kfsbuyzx kxhxx ywvzrfim