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Column definitions include several metadata properties, which store information that is used both in development and at runtime.

Title

The Title property of a column is simply the human-readable name for a column. When a field is placed on a form with the Place with labels option, the label's text property will be initialized to the title property for the column to reach the field is bound. For multilingual applications, it is ideal to populate a column's title property with an i18n message key, thus allowing field labels to default to message key, which is translated at runtime.

Default Format

The Default Format property of a column will enforce the formatting that is used when the column is bound to a field element. The field element's format property will assume the default format of the column unless it is overridden in the element.

Foreign Type

This is a simple metadata property to indicate that a column is a foreign key to another table in the same database. One can set the Foreign Type property to the target table. This provides metadata so developers will know that a column is used as a foreign key. Servoy will use this information when new relations are created between the tables and auto-fill the keys. This property is also used by the mergeRecords method of the databaseManager API to update any affected related records, such that they'll reference a new key.

Exclude Flag

Enabling a column's Excluded Flag will completely exclude a column from the Servoy runtime environment. This means that Servoy will exclude this column for every query that it issues. This option is ideal to enforce that certain columns are never available in a Servoy application.

UUID Flag

Servoy supports the use of Universally Unique Identifiers (UUID). A UUID is a 16-byte number which can be (practically) guaranteed to be unique across computing environments, making it ideal to use for sequences in scenarios where traditional numeric sequences are not adequate, for example when syncing data which is generated offline. It is generally not feasible to store UUIDs as numeric data types because the number is so large. Rather UUIDs are most easily stored as 36-character strings. When using a text column to store UUIDs, one should mark the column's UUID flag. Thus, Servoy will provide programmatic access to this column in the form of a built-in UUID data type, which allows both string and byte representation.

Description

A column's description property is a simple container for additional metadata, such as programmer notes about the column's purpose, etc.

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