The query below lists all columns with JSON data types in PostgreSQL database.
Query
select col.table_schema,
       col.table_name,
       col.ordinal_position as column_id,
       col.column_name,
       col.data_type
from information_schema.columns col
join information_schema.tables tab on tab.table_schema = col.table_schema
                                   and tab.table_name = col.table_name
                                   and tab.table_type = 'BASE TABLE'
where col.table_schema not in ('information_schema', 'pg_catalog')
      and col.data_type = 'json'
order by col.table_schema,
         col.table_name,
         col.ordinal_position;
Columns
- table_schema - name of the schema
- table_name - name of the table
- column_id - column position in table
- column_name - name of the column
- data_type - type of data
Rows
- One row represents one column with a JSON data type
- Scope of rows: all columns containing JSON data types in the database
- Ordered by schema name, table name and column position in table
Sample results

 
                                                                     
                                                                     
                                                                     
                                                                     
                                                                     
                                                                     
                                                                     
                                                                     
                                                                     
                                                                     
                                                                     
                                                                     
                                                                     
                                                                     
                                                                     
                                                                     
                                                                     
                                                                 
                                                             
                                                             
                                                             
                                                             
                                                                 
                                                             
                                                             
                                                                 
                                                             
                                                             
                                                             
                                                             Bart Gawrych
                                                                        Bart Gawrych
                                 PostgreSQL
                                                                PostgreSQL
                                 Oracle database
                                                                                                Oracle database
                                             Teradata
                                                                                                Teradata
                                             MySQL
                                                                                                MySQL