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Index Parameters

Applies to: Windows | Windows Server

Index Parameters

This topic contains parameters that are used for the index.

JET_paramIndexTupleIncrement
132

This parameter specifies the default for the offset increment used to step through the source column value while generating each tuple. For more information, see the JET_TUPLELIMITS structure.

Label Value

Default Value:

1

Type:

Integer

Valid Range:

0 - 32767

Scope:

Instance

Set After JetCreateInstance:

Yes

Set after JetInit:

No

Affects Physical Layout:

No

Affects Reliability:

No

Affects Performance:

No

Affects Resources:

No

Availability:

Windows Vista and later releases

JET_paramIndexTupleStart
133

This parameter specifies the default for the offset in the source column value at which tuple generation will start. For more information, see the JET_TUPLELIMITS structure.

Label Value

Default Value:

0

Type:

Integer

Valid Range:

0 - 32767

Scope:

Instance

Set After JetCreateInstance:

Yes

Set after JetInit:

No

Affects Physical Layout:

No

Affects Reliability:

No

Affects Performance:

No

Affects Resources:

No

Availability:

Windows Vista and later releases

JET_paramIndexTuplesLengthMax
111

This parameter specifies the default for the maximum tuple length in a tuple index. For more information, see the JET_TUPLELIMITS structure.

Windows Vista:  Prior to Windows Vista, setting this parameter to zero would set it back to its default value. For Windows Vista, this is no longer supported.

Label Value

Default Value:

10

Type:

Integer

Valid Range:

Windows 2000, Windows XP and Windows Server 2003:   0, 2-255

Windows Vista:  2-255

Scope:

Instance

Set After JetCreateInstance:

Yes

Set after JetInit:

No

Affects Physical Layout:

No

Affects Reliability:

No

Affects Performance:

No

Affects Resources:

No

Availability:

Windows XP and later releases

JET_paramIndexTuplesLengthMin
110

This parameter specifies the default for the minimum tuple length in a tuple index. See JET_TUPLELIMITS for more information.

Windows Vista:  Prior to Windows Vista, setting this parameter to zero would set it back to its default value. For Windows Vista, this is no longer supported.

Label Value

Default Value:

3

Type:

Integer

Valid Range:

Windows 2000, Windows XP and Windows Server 2003:   0, 2-255

Windows Vista:  2-255

Scope:

Instance

Set After JetCreateInstance:

Yes

Set after JetInit:

No

Affects Physical Layout:

No

Affects Reliability:

No

Affects Performance:

No

Affects Resources:

No

Availability:

Windows XP and later releases

JET_paramIndexTuplesToIndexMax
112

This parameter specifies the default for the maximum length of a source string to break into tuples for a tuple index. See JET_TUPLELIMITS for more information.

Windows Vista:  Prior to Windows Vista, setting this parameter to zero would set it back to its default value. For Windows Vista, this is no longer supported.

Label Value

Default Value:

32767

Type:

Integer

Valid Range:

Windows 2000, Windows XP and Windows Server 2003:  0 – 32767

Windows Vista:  1 – 32767

Scope:

Instance

Set After JetCreateInstance:

Yes

Set after JetInit:

No

Affects Physical Layout:

No

Affects Reliability:

No

Affects Performance:

No

Affects Resources:

No

Availability:

Windows XP and later releases

JET_paramUnicodeIndexDefault
72

This parameter controls the default Unicode parameters used by any index over a Unicode key column. The type of this parameter is JET_UNICODEINDEX and is actually passed using a buffer pointer stored in the integer parameter of JetGetSystemParameter and JetSetSystemParameter. The size of the buffer must equal the size of JET_UNICODEINDEX and must be passed to JetGetSystemParameter using the string buffer size parameter. This is clearly inconsistent but that is the behavior of this parameter.

The default value of this parameter contains an LCID for the U.S. English locale and the following LCMapStringWflags: LCMAP_SORTKEY, NORM_IGNORECASE, NORM_IGNOREKANATYPE, and NORM_IGNOREWIDTH.

Windows 2000:  The SORTID in the LCID is ignored. A SORTID of SORT_DEFAULT is always used.

Windows 2000:  The LCMapStringW flags must contain the following flags: LCMAP_SORTKEY, NORM_IGNORECASE, NORM_IGNOREKANATYPE, and NORM_IGNOREWIDTH. In addition, the LCMapStringWflags may contain the following flags: NORM_IGNORENONSPACE.

Note  If your application wishes to store Unicode data, then it is strongly recommended that you do not rely on the default Unicode parameters for your indexes. The use of U.S. English is tantamount to using the invariant locale and the default LCMapStringWflags are known to seriously interfere with some languages. You should always specify your own settings for the Unicode parameters to JetCreateIndex2 using JET_INDEXCREATE.

Label Value

Default Value:

Special

Type:

JET_UNICODEINDEX* (JET_UNICODEINDEX)

Valid Range:

Special

Scope:

Instance

Set After JetCreateInstance:

Yes

Set after JetInit:

No

Affects Physical Layout:

No

Affects Reliability:

No

Affects Performance:

No

Affects Resources:

No

Availability:

All

Requirements

Requirement Value

Client

Requires Windows Vista, Windows XP, or Windows 2000 Professional.

Server

Requires Windows Server 2008, Windows Server 2003, or Windows 2000 Server.

Header

Declared in Esent.h.

See Also

JET_INDEXCREATE
JET_TUPLELIMITS
JET_UNICODEINDEX
JetCreateInstance
JetGetSystemParameter
JetInit
JetSetSystemParameter