ScyllaDB University LIVE, FREE Virtual Training Event | March 21
Register for Free
ScyllaDB Documentation Logo Documentation
  • Server
  • Cloud
  • Tools
    • ScyllaDB Manager
    • ScyllaDB Monitoring Stack
    • ScyllaDB Operator
  • Drivers
    • CQL Drivers
    • DynamoDB Drivers
  • Resources
    • ScyllaDB University
    • Community Forum
    • Tutorials
Download
ScyllaDB Docs ScyllaDB Open Source CQL Reference JSON Support

Caution

You're viewing documentation for a previous version. Switch to the latest stable version.

JSON Support¶

ScyllaDB introduces JSON support to SELECT and INSERT statements. This support does not fundamentally alter the CQL API (for example, the schema is still enforced). It simply provides a convenient way to work with JSON documents.

SELECT JSON¶

With SELECT statements, the JSON keyword can be used to return each row as a single JSON encoded map. The remainder of the SELECT statement behavior is the same.

The result map keys are the same as the column names in a normal result set. For example, a statement like SELECT JSON a, ttl(b) FROM ... would result in a map with keys "a" and "ttl(b)". However, this is one notable exception: for symmetry with INSERT JSON behavior, case-sensitive column names with upper-case letters will be surrounded with double-quotes. For example, SELECT JSON myColumn FROM ... would result in a map key "\"myColumn\"" (note the escaped quotes).

The map values will JSON-encoded representations (as described below) of the result set values.

INSERT JSON¶

With INSERT statements, the new JSON keyword can be used to enable inserting a JSON encoded map as a single row. The format of the JSON map should generally match that returned by a SELECT JSON statement on the same table. In particular, case-sensitive column names should be surrounded by double-quotes. For example, to insert into a table with two columns named “myKey” and “value”, you would do the following:

INSERT INTO mytable JSON '{ "\"myKey\"": 0, "value": 0}'

By default (or if DEFAULT NULL is explicitly used), a column omitted from the JSON map will be set to NULL, meaning that any pre-existing value for that column will be removed (resulting in a tombstone being created). Alternatively, if the DEFAULT UNSET directive is used after the value, omitted column values will be left unset, meaning that pre-existing values for those columns will be preserved.

JSON Encoding of ScyllaDB Data Types¶

Where possible, ScyllaDB will represent and accept data types in their native JSON representation. ScyllaDB will also accept string representations matching the CQL literal format for all single-field types. For example, floats, ints, UUIDs, and dates can be represented by CQL literal strings. However, compound types, such as collections, tuples, and user-defined types, must be represented by native JSON collections (maps and lists) or a JSON-encoded string representation of the collection.

The following table describes the encodings that ScyllaDB will accept in INSERT JSON values (and fromJson() arguments) as well as the format ScyllaDB will use when returning data for SELECT JSON statements (and fromJson()):

Type

Formats accepted

Return format

Notes

ascii

string

string

Uses JSON’s \u character escape

bigint

integer, string

integer

String must be valid 64 bit integer

blob

string

string

String should be 0x followed by an even number of hex digits

boolean

boolean, string

boolean

String must be “true” or “false”

date

string

string

Date in format YYYY-MM-DD, timezone UTC

decimal

integer, float, string

float

May exceed 32 or 64-bit IEEE-754 floating point precision in client-side decoder

double

integer, float, string

float

String must be valid integer or float

float

integer, float, string

float

String must be valid integer or float

inet

string

string

IPv4 or IPv6 address

int

integer, string

integer

String must be valid 32 bit integer

list

list, string

list

Uses JSON’s native list representation

map

map, string

map

Uses JSON’s native map representation

smallint

integer, string

integer

String must be valid 16 bit integer

set

list, string

list

Uses JSON’s native list representation

text

string

string

Uses JSON’s \u character escape

time

string

string

Time of day in format HH-MM-SS[.fffffffff]

timestamp

integer, string

string

A timestamp. Strings constant allows to input timestamps as dates. Datestamps with format YYYY-MM-DD HH:MM:SS.SSS are returned.

timeuuid

string

string

Type 1 UUID. See constant for the UUID format

tinyint

integer, string

integer

String must be valid 8 bit integer

tuple

list, string

list

Uses JSON’s native list representation

UDT

map, string

map

Uses JSON’s native map representation with field names as keys

uuid

string

string

See constant for the UUID format

varchar

string

string

Uses JSON’s \u character escape

varint

integer, string

integer

Variable length; may overflow 32 or 64 bit integers in client-side decoder

The fromJson() Function¶

The fromJson() function may be used similarly to INSERT JSON, but for a single column value. It may only be used in the VALUES clause of an INSERT statement or as one of the column values in an UPDATE, DELETE, or SELECT statement. For example, it cannot be used in the selection clause of a SELECT statement.

The toJson() Function¶

The toJson() function may be used similarly to SELECT JSON, but for a single column value. It may only be used in the selection clause of a SELECT statement.

  • Apache Cassandra Query Language (CQL) Reference

Copyright

© 2016, The Apache Software Foundation.

Apache®, Apache Cassandra®, Cassandra®, the Apache feather logo and the Apache Cassandra® Eye logo are either registered trademarks or trademarks of the Apache Software Foundation in the United States and/or other countries. No endorsement by The Apache Software Foundation is implied by the use of these marks.

Was this page helpful?

PREVIOUS
Wasm support for user-defined functions
NEXT
Materialized Views
  • Create an issue
  • Edit this page

On this page

  • JSON Support
    • SELECT JSON
    • INSERT JSON
    • JSON Encoding of ScyllaDB Data Types
    • The fromJson() Function
    • The toJson() Function
ScyllaDB Open Source
  • 6.2
    • master
    • 6.2
    • 6.1
    • 6.0
    • 5.4
    • 5.2
    • 5.1
  • Getting Started
    • Install ScyllaDB
      • Launch ScyllaDB on AWS
      • Launch ScyllaDB on GCP
      • Launch ScyllaDB on Azure
      • ScyllaDB Web Installer for Linux
      • Install ScyllaDB Linux Packages
      • Install scylla-jmx Package
      • Run ScyllaDB in Docker
      • Install ScyllaDB Without root Privileges
      • Air-gapped Server Installation
      • ScyllaDB Housekeeping and how to disable it
      • ScyllaDB Developer Mode
    • Configure ScyllaDB
    • ScyllaDB Configuration Reference
    • ScyllaDB Requirements
      • System Requirements
      • OS Support by Linux Distributions and Version
      • Cloud Instance Recommendations
      • ScyllaDB in a Shared Environment
    • Migrate to ScyllaDB
      • Migration Process from Cassandra to ScyllaDB
      • ScyllaDB and Apache Cassandra Compatibility
      • Migration Tools Overview
    • Integration Solutions
      • Integrate ScyllaDB with Spark
      • Integrate ScyllaDB with KairosDB
      • Integrate ScyllaDB with Presto
      • Integrate ScyllaDB with Elasticsearch
      • Integrate ScyllaDB with Kubernetes
      • Integrate ScyllaDB with the JanusGraph Graph Data System
      • Integrate ScyllaDB with DataDog
      • Integrate ScyllaDB with Kafka
      • Integrate ScyllaDB with IOTA Chronicle
      • Integrate ScyllaDB with Spring
      • Shard-Aware Kafka Connector for ScyllaDB
      • Install ScyllaDB with Ansible
      • Integrate ScyllaDB with Databricks
      • Integrate ScyllaDB with Jaeger Server
      • Integrate ScyllaDB with MindsDB
    • Tutorials
  • ScyllaDB for Administrators
    • Administration Guide
    • Procedures
      • Cluster Management
      • Backup & Restore
      • Change Configuration
      • Maintenance
      • Best Practices
      • Benchmarking ScyllaDB
      • Migrate from Cassandra to ScyllaDB
      • Disable Housekeeping
    • Security
      • ScyllaDB Security Checklist
      • Enable Authentication
      • Enable and Disable Authentication Without Downtime
      • Creating a Custom Superuser
      • Generate a cqlshrc File
      • Reset Authenticator Password
      • Enable Authorization
      • Grant Authorization CQL Reference
      • Certificate-based Authentication
      • Role Based Access Control (RBAC)
      • Encryption: Data in Transit Client to Node
      • Encryption: Data in Transit Node to Node
      • Generating a self-signed Certificate Chain Using openssl
      • Configure SaslauthdAuthenticator
    • Admin Tools
      • Nodetool Reference
      • CQLSh
      • Admin REST API
      • Tracing
      • ScyllaDB SStable
      • ScyllaDB Types
      • SSTableLoader
      • cassandra-stress
      • SSTabledump
      • SSTableMetadata
      • ScyllaDB Logs
      • Seastar Perftune
      • Virtual Tables
      • Reading mutation fragments
      • Maintenance socket
      • Maintenance mode
      • Task manager
    • ScyllaDB Monitoring Stack
    • ScyllaDB Operator
    • ScyllaDB Manager
    • Upgrade Procedures
      • ScyllaDB Versioning
      • ScyllaDB Open Source Upgrade
      • ScyllaDB Open Source to ScyllaDB Enterprise Upgrade
      • ScyllaDB Image
      • ScyllaDB Enterprise
    • System Configuration
      • System Configuration Guide
      • scylla.yaml
      • ScyllaDB Snitches
    • Benchmarking ScyllaDB
    • ScyllaDB Diagnostic Tools
  • ScyllaDB for Developers
    • Develop with ScyllaDB
    • Tutorials and Example Projects
    • Learn to Use ScyllaDB
    • ScyllaDB Alternator
    • ScyllaDB Drivers
      • ScyllaDB CQL Drivers
      • ScyllaDB DynamoDB Drivers
  • CQL Reference
    • CQLSh: the CQL shell
    • Appendices
    • Compaction
    • Consistency Levels
    • Consistency Level Calculator
    • Data Definition
    • Data Manipulation
      • SELECT
      • INSERT
      • UPDATE
      • DELETE
      • BATCH
    • Data Types
    • Definitions
    • Global Secondary Indexes
    • Expiring Data with Time to Live (TTL)
    • Functions
    • Wasm support for user-defined functions
    • JSON Support
    • Materialized Views
    • Non-Reserved CQL Keywords
    • Reserved CQL Keywords
    • Service Levels
    • ScyllaDB CQL Extensions
  • Alternator: DynamoDB API in Scylla
    • Getting Started With ScyllaDB Alternator
    • ScyllaDB Alternator for DynamoDB users
  • Features
    • Lightweight Transactions
    • Global Secondary Indexes
    • Local Secondary Indexes
    • Materialized Views
    • Counters
    • Change Data Capture
      • CDC Overview
      • The CDC Log Table
      • Basic operations in CDC
      • CDC Streams
      • CDC Stream Generations
      • Querying CDC Streams
      • Advanced column types
      • Preimages and postimages
      • Data Consistency in CDC
    • Workload Attributes
  • ScyllaDB Architecture
    • Data Distribution with Tablets
    • ScyllaDB Ring Architecture
    • ScyllaDB Fault Tolerance
    • Consistency Level Console Demo
    • ScyllaDB Anti-Entropy
      • ScyllaDB Hinted Handoff
      • ScyllaDB Read Repair
      • ScyllaDB Repair
    • SSTable
      • ScyllaDB SSTable - 2.x
      • ScyllaDB SSTable - 3.x
    • Compaction Strategies
    • Raft Consensus Algorithm in ScyllaDB
    • Zero-token Nodes
  • Troubleshooting ScyllaDB
    • Errors and Support
      • Report a ScyllaDB problem
      • Error Messages
      • Change Log Level
    • ScyllaDB Startup
      • Ownership Problems
      • ScyllaDB will not Start
      • ScyllaDB Python Script broken
    • Upgrade
      • Inaccessible configuration files after ScyllaDB upgrade
    • Cluster and Node
      • Handling Node Failures
      • Failure to Add, Remove, or Replace a Node
      • Failed Decommission Problem
      • Cluster Timeouts
      • Node Joined With No Data
      • NullPointerException
      • Failed Schema Sync
    • Data Modeling
      • ScyllaDB Large Partitions Table
      • ScyllaDB Large Rows and Cells Table
      • Large Partitions Hunting
      • Failure to Update the Schema
    • Data Storage and SSTables
      • Space Utilization Increasing
      • Disk Space is not Reclaimed
      • SSTable Corruption Problem
      • Pointless Compactions
      • Limiting Compaction
    • CQL
      • Time Range Query Fails
      • COPY FROM Fails
      • CQL Connection Table
    • ScyllaDB Monitor and Manager
      • Manager and Monitoring integration
      • Manager lists healthy nodes as down
    • Installation and Removal
      • Removing ScyllaDB on Ubuntu breaks system packages
  • Knowledge Base
    • Upgrading from experimental CDC
    • Compaction
    • Consistency in ScyllaDB
    • Counting all rows in a table is slow
    • CQL Query Does Not Display Entire Result Set
    • When CQLSh query returns partial results with followed by “More”
    • Run ScyllaDB and supporting services as a custom user:group
    • Customizing CPUSET
    • Decoding Stack Traces
    • Snapshots and Disk Utilization
    • DPDK mode
    • Debug your database with Flame Graphs
    • How to Change gc_grace_seconds for a Table
    • Gossip in ScyllaDB
    • Increase Permission Cache to Avoid Non-paged Queries
    • How does ScyllaDB LWT Differ from Apache Cassandra ?
    • Map CPUs to ScyllaDB Shards
    • ScyllaDB Memory Usage
    • NTP Configuration for ScyllaDB
    • Updating the Mode in perftune.yaml After a ScyllaDB Upgrade
    • POSIX networking for ScyllaDB
    • ScyllaDB consistency quiz for administrators
    • Recreate RAID devices
    • How to Safely Increase the Replication Factor
    • ScyllaDB and Spark integration
    • Increase ScyllaDB resource limits over systemd
    • ScyllaDB Seed Nodes
    • How to Set up a Swap Space
    • ScyllaDB Snapshots
    • ScyllaDB payload sent duplicated static columns
    • Stopping a local repair
    • System Limits
    • How to flush old tombstones from a table
    • Time to Live (TTL) and Compaction
    • ScyllaDB Nodes are Unresponsive
    • Update a Primary Key
    • Using the perf utility with ScyllaDB
    • Configure ScyllaDB Networking with Multiple NIC/IP Combinations
  • Reference
    • AWS Images
    • Azure Images
    • GCP Images
    • Configuration Parameters
    • Glossary
    • Limits
    • API Reference (BETA)
    • Metrics (BETA)
  • ScyllaDB FAQ
  • Contribute to ScyllaDB
Docs Tutorials University Contact Us About Us
© 2025, ScyllaDB. All rights reserved. | Terms of Service | Privacy Policy | ScyllaDB, and ScyllaDB Cloud, are registered trademarks of ScyllaDB, Inc.
Last updated on 08 May 2025.
Powered by Sphinx 7.4.7 & ScyllaDB Theme 1.8.6