# Structured data types

These pages describe the two data types available for the OS Emergency Services Gazetteer (OS ESG):

* [LPI (Type 24 Record)](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/os-emergency-services-gazetteer/os-esg-technical-specification/structured-data-types/lpi-type-24-record)
* [Classification (Type 32 Record)](https://docs.os.uk/os-downloads/products/addresses-and-names-portfolio/os-emergency-services-gazetteer/os-esg-technical-specification/structured-data-types/classification-type-32-record)

The attributes associated with each data type are listed on the following pages. The following information can be found about each attribute:

### Name and Definition

The name of the attribute and what it is describing.

### Data Types

The values the attribute can take. For example, a numeric value or a string. This is provided for both data formats – GeoPackage and CSV.

### Precision

The maximum total number of decimal digits to be stored. This number includes both the left and the right sides of the decimal point. The precision must be a value from 1 through the maximum precision of 38. The SQL Server default precision is 18.

### Scale

Scale (*s*) is the number of decimal digits that are stored to the right of the decimal point. This number is subtracted from precision (*p*) to determine the maximum number of digits to the left of the decimal point. Scale must be a value from 0 through *p*, and can only be specified if precision is specified. The default scale is 0 and so 0 <= *s* <= *p*. Maximum storage sizes vary, based on the precision.

### Code List Name

The name of the code list used in association with the attribute (if applicable) and a hyperlink to the page displaying that code list.

### Size / Max Length&#x20;

Values are given here to indicate the maximum length that you will find in the attribute, to aid in developing applications.

### Nullable

A True or False value to denote whether the attribute always has to be populated with a value (False) or can be NULL (True).

### Data Schema Version

The schema version the data above applies to.