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Servoy will read column definitions from relational database tables. The properties that it reads include:

Column Name

This is the name that is returned by the JDBC Driver. The name will always be displayed as lower case. The column name is also used as the Data Provider ID when working with foundsets and records.

Data Provider ID

When set, it is used as data provider ID instead of the column name.

Data Type

While relation databases support many different data types, Servoy will generalize the data type of a column into one of five general types. In this way, Servoy can support a wide range of database vendors. The five generalized data types include the following:

  1. TEXT: Any alpha-numeric characters (i.e. char, varchar, memo, CLOB, etc.)
  2. INTEGER: Whole numbers (i.e. bit, short, long, bigint, etc.)
  3. NUMBER: Decimal numbers (i.e. float, double, etc)
  4. DATETIME: Temporal values (i.e. date, datetime, timestamp, etc.)
  5. MEDIA: Binary data (i.e. BLOB)

Column Length

For certain data types, databases must enforce the amount of storage allocated to single column for a single record. Data types which accommodate variable length entries, such as text, decimal numbers and binary data will have a length property. Servoy will infer and display this property in the column definition.

Row Identifiers

Servoy is designed to work with regular database tables as well as SQL Views. Regular database tables will have a primary key, consisting of one or more columns, who's value uniquely identifies a record in the table. Servoy will infer the primary key from the database table. However, in the case of SQL Views, which don't have a built-in primary key, the developer must specify which column(s) can be considered the unique row identifier.

Null Values Allowed

Relational database tables may enforce non-null constraints on certain columns, typically for primary key and other essential columns. Servoy will infer from any such constraints from database table and reflect

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