DtoColumns Collection
A collection of DtoColumn objects representing all the columns in a table.
Properties
Count | Returns the number of members in a collection. |
Item | Returns a specific member of a DtoColumns collection. |
Methods
Remarks
You obtain this collection from a property of the
DtoTable Object object.
Use the Count property to find the number of members in the collection.
Example
Dim dictionary as new DtoDictionary
dictionary.Open("d:\MyDemodata")
students_table = dictionary.GetTable("STUDENT")
students_cols = students_table.Columns
See Also
Methods Detail
Add method
Add an item to a DtoColumns collection.
Syntax
status = Collection.Add(Object)
Arguments
Collection | DtoColumns collection to which to add object. |
Object | A new DtoColumn object. |
Return Values
result | DtoResult long value indicating the result of the method call. Use the Error property of the
DtoSession Object to obtain a description for the result. |
Remarks
This method takes a parameter of type DtoColumn. Therefore, you are responsible for first instantiating the object and setting its properties before adding it to the collection.
Note You cannot use this method to add columns to preexisting PSQL tables. This method does not alter data or DDF files, and can only be used to add columns in memory before a table is created. See the example for
AddTable method as a reference.
Remove method
Removes an item from a DtoColumns collection.
Syntax
Collection.Remove(column)
Arguments
Collection | DtoColumns collection from which to remove object. |
column | A variant containing either the index (starting with 1) or the name of the item you wish to remove from the DtoColumns collection |
Return Values
result | DtoResult long value indicating the result of the method call. Use the Error property of the
DtoSession Object to obtain a description for the result. |
Remarks
You can pass either a column name or the 1-based ordinal of the item in the DtoColumns collection.
Note You cannot use this method to remove columns from preexisting PSQL tables. This method does not alter data or DDF files, and can only be used to remove columns in memory before a table is created. See the example for
AddTable method as a reference.
Clear method
Removes all items from a DtoColumns collection.
Syntax
result = Collection.Clear
Arguments
In | Collection | DtoColumns or DtoIndexes collection obtained from a DtoTable object |
Return Values
result | DtoResult long value indicating the result of the method call. Use the Error property of the
DtoSession Object to obtain a description for the result. |
Remarks
This method removes all the columns from a table in memory.
Note You cannot use this method to remove columns from preexisting PSQL tables. This method does not alter data or DDF files, and can only be used to remove all columns in memory before a table is created. See the example for
AddTable method as a reference.