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Allowing null values
By default, Sybase does not allow null values in string columns (like VARCHAR
, TEXT
,
etc). You can change this default value for a database using "isql" by issuing
the following command:
sp_dboption databasename, "allow nulls by default", true
In this example "databasename" is your database name.
Large character data
The large character data fields are stored in a column of type TEXT
.
Sybase allows TEXT
fields to be queried only using the SQL
"LIKE
" operator. Queries against these columns that perform
the SQL "IS NULL
" or "IS NOT NULL
" operations are
not allowed by Sybase. The alternative is to specify a column type of VARCHAR
.
However, the maximum allowed size for a VARCHAR
in Sybase is
255 characters. This is not considered a large enough value for the default
size for storing firingParameters, initParameters, descriptions,
etc.
If performing "IS NULL
" and "IS NOT NULL
" type
queries is important and the 255 character limitation is acceptable,
change these column types to VARCHAR
. This should be accomplished
by altering the schema mapping for the Rule bean and then deploying the BRBeans
jar file.
The query APIs (in the com.ibm.websphere.brb.query
package)
allow for "IS NULL
" and "IS NOT NULL
" type queries
to be performed on several of these fields. In addition, the Rule
Management Application allows the firing parameters to be queried
in this manner. These queries will fail on Sybase with the default column
type of TEXT.
Related tasks... | |
Launching the BRBeans Rule Management Application | |
Related concepts... | |
Parent: Database considerations | |
Oracle considerations | |
Informix considerations | |
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