SYSCHECKS
The syschecks system catalog table describes each
check constraint defined in the database. Because the syschecks table
stores both the ASCII text and a binary encoded form of the check
constraint, it contains multiple rows for each check constraint. The syschecks table
has the following columns.
Column | Type | Explanation |
---|---|---|
constrid | INTEGER | Unique code identifying the constraint |
type | CHAR(1) | Form in which the check constraint is stored: B = Binary encoded s = Select T = Text |
seqno | SMALLINT | Line number of the check constraint |
checktext | CHAR(32) | Text of the check constraint |
The text in the checktext column associated
with
B
type in the type column is in computer-readable
format. To view the text associated with a particular check constraint,
use the following query with the appropriate constrid code:
SELECT * FROM syschecks WHERE constrid=10 AND type='T'
Each check constraint described in the syschecks table also has its own row in the sysconstraints table.
A composite index on the constrid, type, and seqno columns allows only unique values.