MS Sql 2005 Text column

[Brian Goldman]

This may have been mentioned before, I couldn't find it. When using a text column I get an error
SqlCommand.Prepare method requires all variable length parameters to have an explicitly set non-zero Size.

Any workaround?

Thanks,
Brian

[Jan Blessenohl]

Hello Brian Goldman,
We need the length definiton of 0 in the mapping file for Text columns. You can do that in the mapping dialog or directly in the mapping file like this:

          <class name="Person">
            <field name="name">
              <extension key="db-column">
                <extension key="db-sql-type" value="TEXT" />
                <extension key="db-length" value="0" />
              </extension>
            </field>
          </class>

Best wishes,
Jan Blessenohl
the Telerik team

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[Jouie]

Hi Jan,

I used your solution above but I got this error:

"Update failed: Telerik.OpenAccess.RT.sql.SQLException: The data types text and varchar are incompatible in the equal to operator.\r\nStatement(s) could not be prepared.\r\n   at Telerik.OpenAccess.RT.Adonet2Generic.Impl.PreparedStatementImp.executeUpdate()\r\n   at OpenAccessRuntime.Relational.conn.PooledPreparedStatement.executeUpdate()\r\n   at OpenAccessRuntime.Relational.RelationalStorageManager.generateUpdates(OID oid, Int32 index, ClassMetaData cmd, PersistGraph graph, Int32[] fieldNos, Boolean haveNewObjects, CharBuf s)\nRow: GenericOID@7 Template template_id=6\nUPDATE [template] SET [content_html]=? WHERE [template_id] = ? AND [content_html]=?\n(set event logging to all to see parameter values) Telerik.OpenAccess.RT.sql.SQLException: The data types text and varchar are incompatible in the equal to operator.\r\nStatement(s) could not be prepared.\r\n   at Telerik.OpenAccess.RT.Adonet2Generic.Impl.PreparedStatementImp.executeUpdate()\r\n   at OpenAccessRuntime.Relational.conn.PooledPreparedStatement.executeUpdate()\r\n   at OpenAccessRuntime.Relational.RelationalStorageManager.generateUpdates(OID oid, Int32 index, ClassMetaData cmd, PersistGraph graph, Int32[] fieldNos, Boolean haveNewObjects, CharBuf s)"

Below is the mapping sample:

 

 

<class name="Template">
     <extension key="db-do-not-create-table" value="true" />
     <extension key="db-table-name" value="template" />
     <field name="templateId">
        <extension key="db-column">
           <extension key="db-type" value="INTEGER" />
           <extension key="db-column-name" value="template_id" />
        </extension>
     </field>
     <field name="contentHtml">
        <extension key="db-column">
           <extension key="db-sql-type" value="TEXT" />
           <extension key="db-length" value="0" />
        </extension>
     </field>
     <field name="contentText">
        <extension key="db-column">
           <extension key="db-sql-type" value="TEXT" />
           <extension key="db-length" value="0" />
        </extension>
     </field>
</class>

Is there a way to set just the primary key as the only parameter in the where clause of generated statement? Or any workaround?

Thanks,

Jouie

[Thomas]

Hi Jouie,

please add an additional

      <extension key="db-type" value="LONGVARCHAR" />

to the respective column  mapping (also doable via the forward mapping dialog). This extension avoids that the column is handled as an updatable column. Please note, that also in your case the db-optimistic-locking with 'changed' seems not to work well as no other columns are then checked; maybe you should switch to a version field for concurrency control.

Kind regards,
Thomas
the Telerik team

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[Thomas]

Hello.

I have exactly the same problem. But all extensions won't help.
This is was an example column looks:

	<field name="vgsEmaUeberwachungsbereich">
	<extension key="db-column">
	<extension key="db-type" value="LONGVARCHAR" />
	<extension key="db-column-name" value="vgs_ema_ueberwachungsbereich" />
	<extension key="db-sql-type" value="TEXT" />
	<extension key="db-length" value="0" />
	</extension>
	</field>

My current workaround is that I store null into the properties which seems to work. How do I solve this so that I can store empty strings ( like string.Empty ) into the db?

Regards,
Thomas

[Thomas]

Hello Thomas,

I've just identified the problem (MSSQL does not allow 0 as a valid size in the ADO parameter) and the next build will contain the patch.
Workaround: Specify a large (10000000) number as the db-length. This will not alter your table.

Sincerely yours,
Thomas
the Telerik team

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