How to Get Particular Object From Jsonb In Postgresql?

10 minutes read

To get a particular object from a JSONB column in PostgreSQL, you can use the -> operator. This operator allows you to access a specific key or attribute within the JSONB data. You simply need to specify the key you are looking for after the operator in order to retrieve the object associated with that key. Additionally, you can use the ->> operator to get the value of a specific key as text. By leveraging these operators, you can easily extract and work with specific objects within JSONB data stored in PostgreSQL.

Best Oracle Database Books of September 2024

1
OCA Oracle Database SQL Exam Guide (Exam 1Z0-071) (Oracle Press)

Rating is 5 out of 5

OCA Oracle Database SQL Exam Guide (Exam 1Z0-071) (Oracle Press)

2
Oracle PL/SQL Programming: Covers Versions Through Oracle Database 12c

Rating is 4.9 out of 5

Oracle PL/SQL Programming: Covers Versions Through Oracle Database 12c

  • O Reilly Media
3
Oracle Database 12c PL/SQL Programming

Rating is 4.8 out of 5

Oracle Database 12c PL/SQL Programming

4
Beginning Oracle Database 12c Administration: From Novice to Professional

Rating is 4.7 out of 5

Beginning Oracle Database 12c Administration: From Novice to Professional

5
Expert Oracle Database Architecture: Techniques and Solutions for High Performance and Productivity

Rating is 4.6 out of 5

Expert Oracle Database Architecture: Techniques and Solutions for High Performance and Productivity

6
Expert Oracle Database Architecture

Rating is 4.5 out of 5

Expert Oracle Database Architecture

  • Apress
7
Oracle Database Application Security: With Oracle Internet Directory, Oracle Access Manager, and Oracle Identity Manager

Rating is 4.4 out of 5

Oracle Database Application Security: With Oracle Internet Directory, Oracle Access Manager, and Oracle Identity Manager

8
Oracle Database 12c PL/SQL Advanced Programming Techniques

Rating is 4.3 out of 5

Oracle Database 12c PL/SQL Advanced Programming Techniques

9
Oracle Database 11g SQL (Oracle Press)

Rating is 4.2 out of 5

Oracle Database 11g SQL (Oracle Press)

10
Oracle 12c For Dummies

Rating is 4.1 out of 5

Oracle 12c For Dummies


How to retrieve a specific element from a JSONB column in PostgreSQL?

To retrieve a specific element from a JSONB column in PostgreSQL, you can use the -> or ->> operators.


Here is an example using the -> operator to retrieve a specific element by key:

1
2
3
SELECT json_column->'key_name'
FROM table_name
WHERE condition;


Here is an example using the ->> operator to retrieve a specific element by key as text:

1
2
3
SELECT json_column->>'key_name'
FROM table_name
WHERE condition;


Make sure to replace json_column with the name of your JSONB column, key_name with the key of the element you want to retrieve, table_name with the name of your table, and condition with any additional conditions you may have for filtering the records.


These operators allow you to access specific elements within a JSONB column in PostgreSQL and retrieve them for further processing or display.


How to fetch a specific attribute from a JSONB object in PostgreSQL?

You can use the ->> operator in PostgreSQL to fetch a specific attribute from a JSONB object.


Here's an example query that demonstrates how to fetch a specific attribute from a JSONB column in a table:

1
2
3
SELECT json_column->>'attribute_name'
FROM your_table
WHERE your_condition;


Replace json_column with the name of the column containing the JSONB object, attribute_name with the name of the attribute you want to fetch, your_table with the name of the table, and your_condition with any conditions you want to apply.


This query will return the value of the specified attribute from the JSONB object in the specified column according to the specified conditions.


How to extract an object from a JSONB column in PostgreSQL?

To extract an object from a JSONB column in PostgreSQL, you can use the -> operator to extract a specific key-value pair from the JSONB column.


For example, if you have a table called my_table with a JSONB column called json_column that contains JSON data like this:

1
2
3
4
5
{
  "id": 123,
  "name": "John Doe",
  "age": 30
}


You can extract the name field from the json_column using the following query:

1
2
SELECT json_column->'name' AS name
FROM my_table;


This will return the value of the name field from the JSON object stored in the json_column.


You can also extract nested objects by chaining the -> operator. For example, if the JSON data in the json_column contains nested objects like this:

1
2
3
4
5
6
7
{
  "id": 123,
  "person": {
    "name": "John Doe",
    "age": 30
   }
}


You can extract the name field from the nested person object using the following query:

1
2
SELECT json_column->'person'->'name' AS name
FROM my_table;


This will return the value of the name field from the nested person object in the JSON data stored in the json_column.


You can also use the jsonb_extract_path function to extract a specific key from a JSON object. The syntax for using this function is as follows:

1
2
SELECT jsonb_extract_path(json_column, 'key1', 'key2', ...) AS value
FROM my_table;


Replace 'key1', 'key2', etc. with the keys you want to extract from the JSON object stored in the json_column.


What is the command to retrieve nested JSON objects in PostgreSQL?

To retrieve nested JSON objects in PostgreSQL, you can use the -> operator. Here is an example command:

1
2
SELECT data->'key1'->'key2' as nested_object
FROM your_table;


In this command, data is the column containing the JSON object, and key1 and key2 are the keys of the nested object you want to retrieve. You can chain multiple -> operators to access nested levels of the JSON object.


How to select specific elements from a JSONB column in PostgreSQL?

To select specific elements from a JSONB column in PostgreSQL, you can use the -> or ->> operators.


Here's an example of how to select specific elements from a JSONB column:

1
2
3
4
SELECT json_column->'key1' AS value1,
       json_column->'key2' AS value2,
       json_column->'key3'->'subkey' AS value3
FROM your_table;


In this example:

  • -> is used to extract a JSON object field by key.
  • ->> is used to extract a JSON object field as text.
  • json_column is the JSONB column in your table.
  • key1, key2, and key3 are the keys you want to select from the JSON object.
  • subkey is a subkey of key3 that you want to extract.


You can customize the above query based on your specific JSON structure and the elements you want to select.

Facebook Twitter LinkedIn Telegram Whatsapp Pocket

Related Posts:

To persist a list of objects as a JSONB field in Hibernate, you can use the @Type annotation provided by Hibernate. By annotating the field with @Type, you can specify that the field should be mapped to a JSONB column in the database. Additionally, you can cus...
To count the keys of a JSONB object in PostgreSQL, you can use the jsonb_object_keys function along with the jsonb_each function.
To query a JSON array in a JSONB column in PostgreSQL, you can use the jsonb_array_elements function. This function allows you to treat a JSON array as a set of rows that you can query individually. You can use it in combination with other JSON functions to fi...