Importing data into Mathesar

Mathesar allows importing data in CSV and JSON format. It also attempts to automatically infer the data type of the columns.

Importing CSV data

Delimiters

Fields in the CSV data may be delimited by any of the following characters:

Name	Character	Notes
Comma	,	A traditional CSV file (a “Comma Separated Value” document)
Tab	(not printable)	This is sometimes referred to as a TSV file (a “Tab Separated Value” document)
Semicolon	;
Colon	:
Pipe	|

Header rows

By default, Mathesar will use the first row of CSV data to name the columns.

If you un-check “Use first row as header”, then Mathesar will generate default names for the columns which you can edit later.

Importing JSON data

The JSON data must be structured in one of the following ways:

• An array of objects

  Each object produces one row in the table, and the object keys become column names. If a key is present is only one object, then the values for that column will be NULL in all other rows.

  [
    {
      "first_name": "Matt",
      "last_name": "Murdock",
      "gender": "Male",
      "friends": ["Stick", "Foggy"]
    },
    {
      "first_name": "John",
      "last_name": "Doe",
      "email": "jd@example.org",
      "gender": "Male"
    }
  ]
  

• A single object

  This is similar to above but produces a table with only one row.

  {
    "name": "John",
    "age": 21,
    "friends": ["Bob", "Mary"]
  }
  

Our goal is to support whatever pandas.json_normalize supports.