Index Properties (OLE DB)

  • Article

The DBPROPSET_INDEX property set contains the following properties. All of these properties are in the Index property group.

Property ID

Description

DBPROP_INDEX_AUTOUPDATE

  • Type: VT_BOOL

  • Typical R/W: R only

  • Description: Auto Update

Notes: For this provider, the value is always VARIANT_TRUE, which indicates that the index is automatically maintained.

DBPROP_INDEX_NULLCOLLATION

  • Type: VT_I4

  • Typical R/W: R only

  • Description: NULL Collation

Notes: Specifies how null values are collated in the index. For this provider, the value is always DBPROPVAL_NC_LOW, which indicates that null values are collated at the low end of the list.

DBPROP_INDEX_NULLS

  • Type: VT_I4

  • Typical R/W: R/W

  • Description: NULL Keys

Notes: Specifies whether null keys are allowed. For this provider, the value is always DBPROPVAL_IN_DISALLOWNULL, which indicates that the index does not allow entries where the key columns are NULL. If you try to insert an index entry with a null key, the provider returns an error. This provider supports indexes that are nullable and indexes where null values are disallowed.

DBPROP_INDEX_TYPE

  • Type: VT_I4

  • Typical R/W: R only

  • Description: Index Type

Notes: Specifies the type of the index.For this provider, the value is always DBPROPVAL_IT_BTREE.

DBPROP_INDEX_UNIQUE

  • Type: VT_BOOL

  • Typical R/W: R/W

  • Description: Unique

  • Notes: Specifies whether index keys must be unique. The provider supports the following values:

    • VARIANT_TRUE, which indicates that the index keys must be unique

VARIANT_FALSE, which indicates that duplicate keys are allowed.