Arnica UnifiedLogon - base data types in data stores
March 8, 2015 by Igor Lozhkin
data stores allow creating data items (columns) using several base data types, which satisfy most custom implementations and use scenarios:
- Character - implemented in database as varchar with specified length up to 254 characters
- Numeric - implemented in database as numeric, with specified scale and precision (total width and decimal places), with maximum data length of 15 digits
- Boolean - implemented in database as bit
- Datetime - implemented in database as datetime
- Text - implemented in database as text, may include characters with variable length up to 2GB
This data store data type standardization is used to make data type management more efficient across Arnica platform applications.
Changing data type is considered a safe operation if:
- Data store has no records
- Data item has null values in all records in the data store
- Data type change results only in the increase of data length, while base data type remains intact (for example from character(20) to character (50))
- Base data type is changed from character, numeric, or Boolean to text
- Base data type is changed from Boolean to character
- Base data type is changed from numeric to character, provided that character data length can accommodate all digits, decimal dot, and +/- signs
All other data type change scenarios should be considered unsafe and data loss should be assumed, although attempts will be made to at least partially migrate data to a new data type.
With large numbers of records, data type migration may take a while, especially when new data type is incompatible with old data type.
All data store data type management is performed using Arnica UnfiedLogon