SqlDB Field Attributes
lazarus / 16-Databases

----------------------------------------------------------------------
RudieD · 2006-03-06 13:41

Does any one know how to extract the Required attribute of a result
field on MySQL 4.1/5.0 database ?

----------------------------------------------------------------------
RudieD · 2006-03-06 20:18

I have now tried to Open "describe TableName" but something is
blocking it with message "Cannot open a non-select statement". Any
other ideas ?

----------------------------------------------------------------------
matthijs · 2006-03-07 07:25

You could check the required property of the field.
Something like:
Code: [Select]
  if SQLQuery1.Fields[0].Required then ShowMessage('required')

----------------------------------------------------------------------
RudieD · 2006-03-07 08:38

Thats the problem, the Required (as well as Prcision) property is not
extracted from the result. It has been hard-code as far as I could
see.
Any other ideas ?

----------------------------------------------------------------------
matthijs · 2006-03-07 11:15

Then you have to ask your DB-server for this information. You could
enter a query likeCode: [Select]SELECT COLUMN_NAME, DATA_TYPE,
IS_NULLABLE, COLUMN_DEFAULT
  FROM INFORMATION_SCHEMA.COLUMNS
  WHERE table_name = 'tbl_name'
  AND table_schema = 'db_name'
  AND column_name LIKE 'column_name'

If Is_Nullable then it will not be a required field.

Information like this can be easily found on online mysql docs.

[edit]Added just one word, but rather important.  :oops:

----------------------------------------------------------------------
RudieD · 2006-03-08 10:32

Thanks matthijs, I'll go have a look there.