Commented by: @asfernandes

> 2) A value with meaning "do not change value of field" which is effectively the same as (1) for inserts and for updates would leave current value as is instead of resetting it to default or provided value.

What a hack. Completely disagree with this request.

Commented by: @aafemt

Can you suggest a better solution which would allow to modify only those fields that were changed by user but still be able to use prepared statements?

Commented by: Sean Leyne (seanleyne)

Dimitry,

I think the responsibility would be yours, to show that Firebird is not supporting functionality that other engine provide.

I am not aware of any other engine that would allow for a DSQL UPDATE statement to include a column with some form of "leave current value untouched" context -- this is what you are effectively proposing.

Commented by: @asfernandes

> Can you suggest a better solution which would allow to modify only those fields that were changed by user but still be able to use prepared statements?

Firebird support list, please.

Commented by: @aafemt

> I am not aware of any other engine that would allow for a DSQL UPDATE statement to include a column with some form of "leave current value untouched" context

Neither do I. But I still think that it could be a handy feature.

Commented by: Sean Leyne (seanleyne)

I believe Adriano is correct, this definitely smells like a "hack". Please bring this forward in the support list.

Commented by: @aafemt

Ok, I'm waiting for answers in support list.

Commented by: @aafemt

Getting back to this ticket:

DB2 docs: https://www.ibm.com/support/knowledgecenter/en/ssw_ibm_i_72/rzajp/rzajpnullvar.htm

"For extended indicators, the indicator values are interpreted as follows:

An indicator value of 0 means the value for the host variable is assigned to the column\.
An indicator value of \-1, \-2, \-3, \-4, or \-6 means the null value is assigned to the column\.
An indicator value of \-5 means the default value for the column is assigned\.
An indicator value of \-7 means that the column is not assigned\. This value causes the column to be treated as though it were not listed in the insert or update column list\. For an INSERT statement it means the default value is used\."

ODBC specs: https://docs.microsoft.com/en-us/sql/odbc/reference/develop-app/using-length-and-indicator-values

"SQL_DEFAULT_PARAM. A procedure is to use the default value of an input parameter in a procedure instead of the value in the corresponding data buffer.

SQL_COLUMN_IGNORE. SQLBulkOperations or SQLSetPos is to ignore the value in the data buffer. When updating a row of data by a call to SQLBulkOperations or SQLSetPos, the column value is not changed. When inserting a new row of data by a call to SQLBulkOperations, the column value is set to its default or, if the column does not have a default, to NULL."