Complete Field Types Guide

What Are Fields?

Technical Definition

Fields are the columns in your database table. Each field stores a specific type of data. Understanding field types helps you:

• Know what kind of data can be stored
• Understand why certain validations exist
• Write better functional specifications

Basic Field Types

Field Type	What It Stores	Example Use	Database Storage
Char	Short text (single line)	Customer name, Reference	VARCHAR (limited characters)
Text	Long text (multiple lines)	Description, Notes, Address	TEXT (unlimited)
Html	Formatted text with styling	Email templates, Product descriptions	TEXT with HTML tags
Integer	Whole numbers only	Quantity, Age, Count	INTEGER
Float	Decimal numbers	Weight, Dimensions	FLOAT/NUMERIC
Monetary	Currency amounts	Price, Total amount	NUMERIC (with currency link)
Boolean	True/False (checkbox)	Is Active, Is Company	BOOLEAN
Date	Date only (no time)	Birth date, Deadline	DATE
Datetime	Date and time	Order date, Last login	TIMESTAMP
Selection	Predefined choices	Status, Type, Priority	VARCHAR (stores key)
Binary	File attachments	PDF, Excel, Documents	BYTEA or file system
Image	Image files	Product image, Avatar	BYTEA (with auto-resize)
Json	Structured data	Complex configurations	JSONB
Properties	Dynamic sub-fields	Custom fields per project	JSONB

Field Type Details with Examples

Char vs Text - When to Use Which?

Use Char For	Use Text For
Names (max ~255 chars)	Descriptions (unlimited)
Reference numbers	Notes and comments
Email addresses	Full addresses
Phone numbers	Terms and conditions

Key Difference

Char shows as a single-line input. Text shows as a multi-line textarea.

Selection Field - The Dropdown

Selection fields store a key internally but display a label to users.

Example: Order Status

What User Sees	What's Stored in Database
Quotation	draft
Quotation Sent	sent
Sales Order	sale
Cancelled	cancel

Why This Matters

When filtering or searching via API/code, you must use the technical key (draft), not the label (Quotation).

Monetary Field - More Than Just a Number

A Monetary field is linked to a currency field. This allows:

• Proper currency symbol display (EUR, USD, INR)
• Correct decimal places (2 for EUR, 0 for JPY)
• Currency conversion calculations

Example: Sale Order has amount_total (Monetary) linked to currency_id (Many2one to res.currency)

Properties Field - Dynamic Custom Fields

Properties Field

The Properties field allows creating custom sub-fields per record without database changes.

Use Case: Different projects need different custom fields:

• Project "Website Redesign" needs fields: Browser compatibility, Responsive breakpoints
• Project "ERP Implementation" needs fields: Go-live date, Training hours

With Properties, each project can have its own custom fields, and all tasks in that project inherit them!

Common Field Attributes

Every field in Odoo can have attributes that control its behavior. Understanding these is crucial for functional consultants.

Attribute	What It Does	Example	Functional Impact
string	Label shown to users	string="Customer Name"	What appears on forms/lists
required	Must have a value	required=True	Can't save record without it
readonly	Can't be edited	readonly=True	Display only, no editing
default	Pre-filled value	default="draft"	New records start with this value
help	Tooltip on hover	help="Enter name"	Shows info icon with explanation
copy	Include when duplicating	copy=False	Reference numbers shouldn't copy
index	Create DB index	index=True	Faster searches on this field
tracking	Log changes in chatter	tracking=True	Shows "Status: Draft → Confirmed"
groups	Restrict visibility	groups="base.group_system"	Only admins see this field

Required vs Default - Common Confusion

• required=True: User MUST provide a value (even if there's a default)
• default=value: Pre-fills the field, but user can leave it empty (unless also required)
• Both together: Field is pre-filled AND mandatory

Example: Sale Order state has default='draft' and required=True - it always starts as draft and must have a state.

Field Sizes and Limits

Field Type	Default Limit	Can Customize?	Notes
Char	No limit (was 256)	Yes (size=N)	Since Odoo 12, no default limit
Text	Unlimited	No	Use for long content
Integer	-2B to +2B	No	32-bit signed integer
Float	~15 digits precision	Yes (digits)	digits=(16, 2) = 16 total, 2 decimal
Monetary	Currency-dependent	Auto	Uses currency's decimal places
Binary	~1GB (PostgreSQL)	No	Large files stored externally
Image	Auto-resized	Yes	max_width, max_height attributes

Practical Examples by Business Scenario

Scenario: Product Catalog

Field Name	Type	Why This Type?
name	Char	Short product name, single line
description_sale	Text	Long description for quotes
list_price	Float	Price without currency formatting
standard_price	Float	Cost price (company_dependent)
qty_available	Float	Stock can be fractional (0.5 kg)
active	Boolean	Archive/unarchive products
type	Selection	Consumable/Service/Storable
image_1920	Image	Product photo with auto-resize
barcode	Char	EAN/UPC code, indexed for scanning

Scenario: HR Employee

Field Name	Type	Why This Type?
name	Char	Employee's full name
work_email	Char	Email with validation widget
birthday	Date	Only date needed, no time
gender	Selection	male/female/other choices
notes	Text	HR notes, can be lengthy
certificate	Selection	Education level dropdown
resume_line_ids	One2many	Multiple resume entries
image_1920	Image	Employee photo

Float Precision - The Decimal Problem

Why Float Precision Matters

Float fields can cause unexpected rounding issues. Consider this:

Unit Price: 10.00
Quantity: 3
Expected Total: 30.00
Actual (with float errors): 29.999999999997

Solution: Use the digits attribute to control precision:

• digits=(16, 2) = 16 total digits, 2 after decimal (standard for prices)
• digits='Product Price' = Uses named precision from settings
• digits='Product Unit of Measure' = Higher precision for quantities

Named Decimal Precisions in Odoo

Precision Name	Default Digits	Used For
Product Price	2	Prices, unit costs
Product Unit of Measure	5	Quantities (allows 0.00001)
Discount	2	Percentage discounts
Stock Weight	2	Product weights

Configuration

These can be configured in Settings → Technical → Database Structure → Decimal Accuracy

Date and Datetime - Timezone Handling

Critical: Timezone Behavior

Field Type	Storage	Display
Date	Stored as-is (no timezone)	Shows same date everywhere
Datetime	Stored in UTC	Converted to user's timezone

Example Problem: A meeting scheduled at "2024-01-15 10:00" in India (UTC+5:30) is stored as "2024-01-15 04:30" UTC. A user in New York (UTC-5) sees it as "2024-01-14 23:30"!

Solution: Use Date for deadlines/birthdays, Datetime for appointments/timestamps.

Selection Fields - Best Practices

Selection Field Structure

Selection fields have a list of (key, label) pairs:

state = fields.Selection([
    ('draft', 'Draft'),
    ('confirmed', 'Confirmed'),
    ('done', 'Done'),
    ('cancel', 'Cancelled'),
], default='draft')

Key Rules:

• Keys: lowercase, no spaces, use underscores (stored in DB)
• Labels: Human-readable, translatable (shown to users)
• Keys can't be changed after data exists (would lose data!)
• Labels can be changed anytime (just UI text)

Adding Options to Existing Selection Fields

You can extend selection fields using selection_add:

# Original field has: draft, confirmed, done
# Your module adds: on_hold

state = fields.Selection(
    selection_add=[('on_hold', 'On Hold')],
    ondelete={'on_hold': 'set default'}
)

ondelete Parameter

The ondelete tells Odoo what to do if the module is uninstalled - set records to default state.

Binary and Image Fields

Binary vs Image - When to Use Which

Use Binary For	Use Image For
PDF documents	Product photos
Excel files	Employee avatars
Any non-image file	Company logos
Images that shouldn't be resized	Any image that needs thumbnails

Image Field Auto-Resize

Image fields automatically create multiple sizes:

• image_1920 - Original/large (max 1920px)
• image_1024 - Medium (max 1024px)
• image_512 - Small (max 512px)
• image_256 - Thumbnail (max 256px)
• image_128 - Icon (max 128px)

Performance Tip

Always use the smallest size needed. Don't load image_1920 for a list view thumbnail!

Field Type Decision Matrix

Quick Reference: Which Field Type to Use?

I need to store...	Use This Type	Not This
A name or title	Char	Text (overkill)
A description or notes	Text	Char (too limited)
A price with currency	Monetary	Float (loses currency)
A percentage	Float	Integer (no decimals)
A count or quantity (whole)	Integer	Float (unnecessary)
A quantity (can be partial)	Float	Integer (can't do 0.5)
A yes/no choice	Boolean	Selection (overkill)
A status with 3+ options	Selection	Char (no validation)
A birthday	Date	Datetime (has TZ issues)
An appointment time	Datetime	Date (loses time)
A document attachment	Binary	Char (can't store files)
A photo/logo	Image	Binary (no auto-resize)
Rich formatted text	Html	Text (loses formatting)

Company-Dependent Fields

What Are Company-Dependent Fields?

In a multi-company environment, some fields need to store different values for each company. These are called company_dependent fields (formerly called "Property" fields).

How It Works

When a field has company_dependent=True:

• The value is stored per-company in a JSONB column
• Each user sees the value for their active company
• Changing companies shows different values automatically

Common Company-Dependent Fields

Model	Field	Why Company-Dependent?
product.template	standard_price	Different cost in each warehouse/company
product.template	property_account_income_id	Different income accounts per company
product.template	property_account_expense_id	Different expense accounts per company
res.partner	property_account_receivable_id	Different AR accounts per company
res.partner	property_account_payable_id	Different AP accounts per company
stock.location	valuation_in_account_id	Different valuation accounts

Database Storage

Company-dependent fields are stored as JSONB with company IDs as keys:

{
  "1": 150.00,    // Company 1: Cost is 150
  "2": 175.50,   // Company 2: Cost is 175.50
  "3": 140.00     // Company 3: Cost is 140
}

For Functional Consultants

When exporting data or creating reports involving company-dependent fields:

• The value shown depends on the user's active company
• Direct SQL queries need to parse JSONB by company ID
• Always verify which company's data you're viewing!

Common Mistakes with Field Types

Wrong Approach: Using Char for Prices

price = fields.Char()

Problem: Can't calculate, sort, or format properly. "100" comes before "20" alphabetically!

Correct:

price = fields.Monetary(currency_field='currency_id')

Benefit: Proper calculations, sorting, currency symbols.

Wrong Approach: Using Text for Emails

email = fields.Text()

Problem: Multi-line input, no email validation, wastes space.

Correct:

email = fields.Char()
# In view: widget="email"

Benefit: Single line, clickable mailto link, proper validation.

Wrong Approach: Datetime for Deadlines

deadline = fields.Datetime()

Problem: "Due Jan 15" might show as "Due Jan 14" in different timezones!

Correct:

deadline = fields.Date()

Benefit: "Due Jan 15" is Jan 15 everywhere in the world.

Wrong Approach: Float for Quantities Without Precision

qty = fields.Float()

Problem: May get rounding errors like 2.9999999 instead of 3.0

Correct:

qty = fields.Float(digits='Product Unit of Measure')

Benefit: Uses named precision (5 decimals) for consistent rounding.

Knowledge Check

Q1: Which field type for Product Price?

Answer: Monetary

Monetary fields handle currency formatting, rounding rules, and multi-currency calculations automatically. Float would lose precision and not show currency symbols.

Q2: Which field type for Deadlines?

Answer: Date

Date fields store only the date without time, so "Jan 15" is Jan 15 for everyone. Datetime would shift based on timezone.

Q3: What's the difference between Html and Text?

Answer: Html allows rich formatting and is sanitized; Text is plain text

Html fields provide a rich text editor and sanitize content to prevent XSS attacks. Text is for multi-line plain text like notes or descriptions.

Q4: What does tracking=True do on a field?

Answer: Logs changes in the chatter

When a tracked field changes, Odoo automatically posts a message in the chatter showing the old and new values, like "Status: Draft → Confirmed".

Q5: Why use digits='Product Price' instead of digits=(16, 2)?

Answer: Named precision is centrally configurable

Using a named precision allows administrators to change decimal places globally in Settings → Technical → Decimal Accuracy, affecting all fields using that precision.

Q6: What makes a field "company_dependent"?

Answer: It stores different values per company

Company-dependent fields (like standard_price on products) store values in JSONB format with company IDs as keys, allowing each company to have its own value.

Q7: When should you use Image instead of Binary?

Answer: When you need automatic resizing and thumbnails

Image fields automatically create multiple sizes (1920, 1024, 512, 256, 128 pixels). Use for photos, logos, avatars. Binary is for documents like PDFs.

Q8: Can you change a Selection field's key after data exists?

Answer: No - you would lose data

Selection keys are stored in the database. Changing a key would orphan existing records. You can only change labels (the display text) safely.