Join us on
Star us on
Get Started
Slack
GitHub
Get Started
v2.5 (latest) v2.2 (stable) v2.1 (earlier version) v2.0 (earlier version) v1.3 (earlier version)
  • YUGABYTEDB CORE
    • Quick start
      • 1. Install YugabyteDB
      • 2. Create a local cluster
      • 3. Explore distributed SQL
      • 4. Build an application
        • Java
        • NodeJS
        • Go
        • Python
        • Ruby
        • C#
        • PHP
        • C++
        • C
        • Scala
    • Explore features
      • Linear scalability
      • Fault tolerance
      • Global distribution
      • Auto sharding
      • Follower reads
      • Observability
      • Colocated tables
      • Change data capture (CDC)
      • Two data center (2DC)
    • Develop
      • Learn app development
        • 1. SQL vs NoSQL
        • 2. Data modeling
        • 3. Data types
        • 4. ACID transactions
        • 5. Aggregations
        • 6. Batch operations
        • 7. Date and time
        • 8. Strings and text
        • 9. TTL for data expiration
      • Ecosystem integrations
        • Apache Kafka
        • Apache Spark
        • JanusGraph
        • KairosDB
        • Presto
        • Metabase
      • Build GraphQL apps
        • Hasura
        • Prisma
      • Real-world examples
        • E-Commerce app
        • IoT fleet management
        • Retail Analytics
      • Explore sample apps
      • Best practices
    • Migrate
      • Migration Process
      • Migrating From PostgreSQL
        • Schema Migration
        • App Migration
        • Export Data
        • Prepare Cluster
        • Import Data
        • Verify Migration
    • Deploy
      • Deployment checklist
      • Manual deployment
        • 1. System configuration
        • 2. Install software
        • 3. Start YB-Masters
        • 4. Start YB-TServers
        • 5. Verify deployment
      • Kubernetes
        • Single-zone
          • Open Source
          • Amazon EKS
          • Google Kubernetes Engine
          • Azure Kubernetes Service
        • Multi-zone
          • Amazon EKS
          • Google Kubernetes Engine
        • Multi-cluster
          • Google Kubernetes Engine
        • Best practices
        • Connect clients
      • Docker
      • Public clouds
        • Amazon Web Services
        • Google Cloud Platform
        • Microsoft Azure
      • Multi-DC deployments
        • Three+ data center (3DC)
        • Two data center (2DC)
        • Read replica clusters
      • Change data capture (CDC)
        • CDC to Kafka
    • Benchmark
      • TPC-C
      • sysbench
      • YCSB
      • Key-value workload
      • Large datasets
      • Scalability
        • Scaling queries
      • Resilience
        • Jepsen testing
    • Secure
      • Security checklist
      • Authentication
        • Authentication
        • Fine-grained authentication
      • Encryption in transit
        • Create client certificates
        • Create server certificates
        • Enable server-to-server encryption
        • Enable client-to-server encryption
        • Connect to clusters
      • Encryption at rest
      • Authorization
        • RBAC model
        • Create roles
        • Grant privileges
      • Audit logging
    • Manage
      • Back up and restore
        • Back up data
        • Restore data
        • Snapshot and restore data
      • Migrate data
        • Bulk import
        • Bulk export
      • Change cluster configuration
      • Diagnostics reporting
      • Upgrade a deployment
    • Troubleshoot
      • Troubleshooting
      • Cluster level issues
        • YCQL connection issues
        • YEDIS connection Issues
        • Recover tserver/master
      • Node level issues
        • Check servers
        • Inspect logs
        • System statistics
        • Disk failure
    • Contribute
  • YUGABYTE PLATFORM
    • Yugabyte Platform
      • Overview
        • Install
        • Configure
      • Install Yugabyte Platform
        • Prerequisites
        • Prepare the environment
        • Install software
        • Prepare nodes (on-prem)
        • Uninstall software
      • Configure Yugabyte Platform
        • Create admin user
        • Configure the cloud provider
        • Configure the backup target
        • Configure alerts and health checking
        • Create and edit instance tags
      • Create deployments
        • Multi-zone universe
        • Multi-region universe
        • Read replica cluster
      • Manage deployments
        • Start and stop processes
        • Add a node
        • Remove a node
        • Edit a universe
        • Edit configuration flags
        • Upgrade the YugabyteDB software
        • Delete a universe
        • Migrate to Helm 3
      • Back up and restore universes
        • Configure backup storage
        • Back up universe data
        • Restore universe data
        • Schedule data backups
      • Security
        • Security checklist
        • Customize ports
        • Authorization platform
        • Create a KMS configuration
        • Enable encryption at rest
        • Enable encryption in transit (TLS)
        • Network security
      • Troubleshoot
        • Install and upgrade
        • Universe
      • Administer Yugabyte Platform
        • Back up and restore Yugabyte Platform
  • YUGABYTE CLOUD
    • Yugabyte Cloud
      • Free tier
      • Create clusters
      • Monitor clusters
      • Create databases
      • Manage database access
      • Connect to clusters
  • REFERENCE
    • Reference
    • Architecture
      • Design goals
      • Key concepts
        • Universe
        • YB-TServer Service
        • YB-Master Service
      • Layered architecture
      • Query layer
        • Overview
      • DocDB transactions layer
        • Transactions overview
        • Transaction isolation levels
        • Explicit locking
        • Single-row transactions
        • Distributed transactions
        • Transactional IO path
      • DocDB sharding layer
        • Hash & range sharding
        • Tablet splitting
        • Colocated tables
      • DocDB replication layer
        • Replication
        • xCluster replication
        • Read replicas
        • Change data capture (CDC)
      • DocDB storage layer
        • Persistence
        • Performance
    • APIs
      • YSQL
        • Statements
          • ABORT
          • ALTER DATABASE
          • ALTER DEFAULT PRIVILEGES
          • ALTER DOMAIN
          • ALTER GROUP
          • ALTER POLICY
          • ALTER ROLE
          • ALTER SEQUENCE
          • ALTER TABLE
          • ALTER USER
          • BEGIN
          • COMMENT
          • COMMIT
          • COPY
          • CREATE AGGREGATE
          • CREATE CAST
          • CREATE DATABASE
          • CREATE DOMAIN
          • CREATE EXTENSION
          • CREATE FUNCTION
          • CREATE GROUP
          • CREATE INDEX
          • CREATE OPERATOR
          • CREATE OPERATOR CLASS
          • CREATE POLICY
          • CREATE PROCEDURE
          • CREATE ROLE
          • CREATE RULE
          • CREATE SCHEMA
          • CREATE SEQUENCE
          • CREATE TABLE
          • CREATE TABLE AS
          • CREATE TRIGGER
          • CREATE TYPE
          • CREATE USER
          • CREATE VIEW
          • DEALLOCATE
          • DELETE
          • DO
          • DROP AGGREGATE
          • DROP CAST
          • DROP DATABASE
          • DROP DOMAIN
          • DROP EXTENSION
          • DROP FUNCTION
          • DROP GROUP
          • DROP OPERATOR
          • DROP OPERATOR CLASS
          • DROP OWNED
          • DROP POLICY
          • DROP PROCEDURE
          • DROP ROLE
          • DROP RULE
          • DROP SEQUENCE
          • DROP TABLE
          • DROP TRIGGER
          • DROP TYPE
          • DROP USER
          • END
          • EXECUTE
          • EXPLAIN
          • GRANT
          • INSERT
          • LOCK
          • PREPARE
          • REASSIGN OWNED
          • RESET
          • REVOKE
          • ROLLBACK
          • SELECT
          • SET
          • SET CONSTRAINTS
          • SET ROLE
          • SET SESSION AUTHORIZATION
          • SET TRANSACTION
          • SHOW
          • SHOW TRANSACTION
          • TRUNCATE
          • UPDATE
        • Data types
          • Array
            • array[] constructor
            • Literals
              • Text typecasting and literals
              • Array of primitive values
              • Row
              • Array of rows
            • FOREACH loop (PL/pgSQL)
            • array of DOMAINs
            • Functions and operators
              • ANY and ALL
              • Array comparison
              • Array slice operator
              • Array concatenation
              • Array properties
              • array_agg(), unnest(), generate_subscripts()
              • array_fill()
              • array_position(), array_positions()
              • array_remove()
              • array_replace() / set value
              • array_to_string()
              • string_to_array()
          • Binary
          • Boolean
          • Character
          • Date and time
          • JSON
            • JSON literals
            • Primitive and compound data types
            • Code example conventions
            • Indexes and check constraints
            • Functions & operators
              • ::jsonb, ::json, ::text (typecast)
              • ->, ->>, #>, #>> (JSON subvalues)
              • - and #- (remove)
              • || (concatenation)
              • = (equality)
              • @> and <@ (containment)
              • ? and ?| and ?& (key or value existence)
              • array_to_json()
              • jsonb_agg()
              • jsonb_array_elements()
              • jsonb_array_elements_text()
              • jsonb_array_length()
              • jsonb_build_object()
              • jsonb_build_array()
              • jsonb_each()
              • jsonb_each_text()
              • jsonb_extract_path()
              • jsonb_extract_path_text() and json_extract_path_text()
              • jsonb_object()
              • jsonb_object_agg()
              • jsonb_object_keys()
              • jsonb_populate_record()
              • jsonb_populate_recordset()
              • jsonb_pretty()
              • jsonb_set() and jsonb_insert()
              • jsonb_strip_nulls()
              • jsonb_to_record()
              • jsonb_to_recordset()
              • jsonb_typeof()
              • row_to_json()
              • to_jsonb()
          • Money
          • Numeric
          • Serial
          • UUID
        • Functions and operators
          • currval()
          • lastval()
          • nextval()
          • Window functions
            • Informal functionality overview
            • Invocation SQL syntax and semantics
            • Per function signature and purpose
              • row_number(), rank() and dense_rank()
              • percent_rank(), cume_dist() and ntile()
              • first_value(), nth_value(), last_value()
              • lag(), lead()
              • Tables for the code examples
                • table t1
                • table t2
                • table t3
                • table t4
            • Analyzing a normal distribution
              • Bucket allocation scheme
              • do_clean_start.sql
              • cr_show_t4.sql
              • cr_dp_views.sql
              • cr_int_views.sql
              • cr_pr_cd_equality_report.sql
              • cr_bucket_using_width_bucket.sql
              • cr_bucket_dedicated_code.sql
              • do_assert_bucket_ok
              • cr_histogram.sql
              • cr_do_ntile.sql
              • cr_do_percent_rank.sql
              • cr_do_cume_dist.sql
              • do_populate_results.sql
              • do_report_results.sql
              • do_compare_dp_results.sql
              • do_demo.sql
              • Reports
                • Histogram report
                • dp-results
                • compare-dp-results
                • int-results
        • Extensions
        • Keywords
        • Reserved names
      • YCQL
        • ALTER KEYSPACE
        • ALTER ROLE
        • ALTER TABLE
        • CREATE INDEX
        • CREATE KEYSPACE
        • CREATE ROLE
        • CREATE TABLE
        • CREATE TYPE
        • DROP INDEX
        • DROP KEYSPACE
        • DROP ROLE
        • DROP TABLE
        • DROP TYPE
        • GRANT PERMISSION
        • GRANT ROLE
        • REVOKE PERMISSION
        • REVOKE ROLE
        • USE
        • INSERT
        • SELECT
        • EXPLAIN
        • UPDATE
        • DELETE
        • TRANSACTION
        • TRUNCATE
        • Simple expressions
        • Subscripted expressions
        • Function call
        • Operators
        • BLOB
        • BOOLEAN
        • Collection
        • FROZEN
        • INET
        • Integer and counter
        • Non-integer
        • TEXT
        • DATE, TIME, and TIMESTAMP
        • UUID and TIMEUUID
        • JSONB
        • Date and time
        • BATCH
    • CLIs
      • yb-ctl
      • yb-docker-ctl
      • ysqlsh
      • ycqlsh
      • yb-admin
      • yb-ts-cli
      • ysql_dump
      • ysql_dumpall
    • Configuration
      • yb-tserver
      • yb-master
      • yugabyted
      • Default ports
    • Drivers
      • Client drivers for YSQL API
      • YugabyteDB JDBC Driver
      • Client drivers for YCQL
      • Spring Data YugabyteDB
    • Connectors
      • Kafka Connect YugabyteDB
    • Third party tools
      • DBeaver
      • DbSchema
      • pgAdmin
      • SQL Workbench/J
      • TablePlus
      • Visual Studio Code
    • Sample datasets
      • Chinook
      • Northwind
      • PgExercises
      • SportsDB
  • RELEASES
    • Releases
    • Releases overview
    • Release versioning
    • What's new
      • 2.3 (latest)
      • 2.2 (stable)
    • Earlier releases
      • v2.1.8
      • v2.1.6
      • v2.1.5
      • v2.1.4
      • v2.1.3
      • v2.1.2
      • v2.1.1
      • v2.1.0
      • v2.0.11
      • v2.0.10
      • v2.0.9
      • v2.0.8
      • v2.0.7
      • v2.0.6
      • v2.0.5
      • v2.0.3
      • v2.0.1
      • v2.0.0
      • v1.3.1
      • v1.3.0
      • v1.2.12
      • v1.2.11
      • v1.2.10
      • v1.2.9
      • v1.2.8
      • v1.2.6
      • v1.2.5
      • v1.2.4
  • FAQ
    • Comparisons
      • Amazon Aurora
      • Google Cloud Spanner
      • CockroachDB
      • TiDB
      • Vitess
      • MongoDB
      • FoundationDB
      • Amazon DynamoDB
      • Azure Cosmos DB
      • Apache Cassandra
      • PostgreSQL
      • Redis in-memory store
      • Apache HBase
    • FAQs
      • General FAQ
      • Operations FAQ
      • API compatibility FAQ
      • Yugabyte Platform FAQ
  • MISC
    • YEDIS
      • Quick start
      • Develop
        • Build an application
        • C#
        • C++
        • Go
        • Java
        • NodeJS
        • Python
      • API reference
        • APPEND
        • AUTH
        • CONFIG
        • CREATEDB
        • DELETEDB
        • LISTDB
        • SELECT
        • DEL
        • ECHO
        • EXISTS
        • EXPIRE
        • EXPIREAT
        • FLUSHALL
        • FLUSHDB
        • GET
        • GETRANGE
        • GETSET
        • HDEL
        • HEXISTS
        • HGET
        • HGETALL
        • HINCRBY
        • HKEYS
        • HLEN
        • HMGET
        • HMSET
        • HSET
        • HSTRLEN
        • HVALS
        • INCR
        • INCRBY
        • KEYS
        • MONITOR
        • PEXPIRE
        • PEXPIREAT
        • PTTL
        • ROLE
        • SADD
        • SCARD
        • RENAME
        • SET
        • SETEX
        • PSETEX
        • SETRANGE
        • SISMEMBER
        • SMEMBERS
        • SREM
        • STRLEN
        • ZRANGE
        • TSADD
        • TSCARD
        • TSGET
        • TSLASTN
        • TSRANGEBYTIME
        • TSREM
        • TSREVRANGEBYTIME
        • TTL
        • ZADD
        • ZCARD
        • ZRANGEBYSCORE
        • ZREM
        • ZREVRANGE
        • ZSCORE
        • PUBSUB
        • PUBLISH
        • SUBSCRIBE
        • UNSUBSCRIBE
        • PSUBSCRIBE
        • PUNSUBSCRIBE
    • Legal
      • Third party software
> APIs > YSQL > Data types > JSON >

Code example conventions

Attention

This page documents an earlier version. Go to the latest (v2.3) version.
  • Note about the code examples
  • Note about SQL array literals

Note about the code examples

The functionality of each operator and function is illustrated by a code example of this form:

[function or operator]
  acts on
[argument (list)]
  to produce
[result value]

It's insufficient to present such examples in the style "run this SQL at the ysqlsh prompt" followed by "see this result". A SQL-only demonstration has these disadvantages:

  • It's hard to establish and advertise data type information without inserting into appropriately defined table columns. This brings distracting verbosity.
  • The only way to build an expression from subexpressions, in pursuit of clarity, is to use scalar subqueries, named in a with clause. This, again, is so verbose that it obscures, rather than helps, clarity.
  • This insufficiency is especially bothersome when the aim is to show how the output of a particular function depends upon the choice of value for an optional boolean parameter that conditions is behavior using, therefore, the same input JSON value in two function invocations.
  • The result is a non-negotiable typecast to text to print to the screen, with additional distracting conventions like, for example, inserting a space at the start of each printed line, showing the boolean value TRUE as the text value t, showing NULL as just an absence, and showing a newline as the text value +.

For these reasons, each code example is presented as a DO block with this pattern:

  • Each input value is declared using the appropriate SQL data type (sometimes building such values bottom-up from declared simpler values).
  • The output of the operator or expression is assigned to a variable of the appropriate data type.
  • The expected output is declared as a value of the same data type.
  • An ASSERT is used to show that the produced value is equal to the expected value, using an IS NULL comparison where appropriate.

Note about SQL array literals

RFC 7159 defines the syntax for a JSON array as a comma-separated list of items surrounded by [] and the syntax for a JSON object as a comma-separated list of key-value pairs surrounded by {}. The literal for a SQL array is a text value with an inner syntax, typecasted the array's data type: the value starts with { and ends with } and contains a comma-separated list whose items are not themselves single-quoted but are all taken to be values of the array's data type. So this SQL array value:

array['a', 'b', 'c']::text[]

can also be written thus:

'{a, b, c}'::text[]

See the section Creating an array value using a literal for more information on this topic. This dramatic context-sensitive difference in meaning of '{...}' might confuse the reader. Therefore, in the major section "JSON data types and functionality", the array[...] constructor form will be used for a SQL array value—and the use of the '{...}' SQL array literal will be avoided.

The fact that a JSON array can have subvalues of mixed data type but a SQL array can have only elements of the same data type means that special steps have to be taken when the goal is to construct a JSON array mixed subvalue data type from SQL values.

  • Note about the code examples
  • Note about SQL array literals
Ask our community
  • Slack
  • Github
  • Forum
  • StackOverflow
Yugabyte
Contact Us
Copyright © 2017-2020 Yugabyte, Inc. All rights reserved.