/// <summary>
/// Gets the NATIVE_indexcolumn structure that represents the object.
/// </summary>
/// <param name="handles">GC handle collection to add any pinned handles.</param>
/// <returns>The NATIVE_indexcolumn structure.</returns>
internal NATIVE_INDEX_RANGE GetNativeIndexRange(ref GCHandleCollection handles)
{
NATIVE_INDEX_RANGE indexRange = new NATIVE_INDEX_RANGE();
NATIVE_INDEX_COLUMN[] nativeColumns;
if (this.startColumns != null)
{
nativeColumns = new NATIVE_INDEX_COLUMN[this.startColumns.Length];
for (int i = 0; i < this.startColumns.Length; i++)
{
nativeColumns[i] = this.startColumns[i].GetNativeIndexColumn(ref handles);
}
indexRange.rgStartColumns = handles.Add(nativeColumns);
indexRange.cStartColumns = (uint)this.startColumns.Length;
}
if (this.endColumns != null)
{
nativeColumns = new NATIVE_INDEX_COLUMN[this.endColumns.Length];
for (int i = 0; i < this.endColumns.Length; i++)
{
nativeColumns[i] = this.endColumns[i].GetNativeIndexColumn(ref handles);
}
indexRange.rgEndColumns = handles.Add(nativeColumns);
indexRange.cEndColumns = (uint)this.endColumns.Length;
}
return(indexRange);
}
/// <summary>
/// If the records with the specified key ranges are not in the
/// buffer cache then start asynchronous reads to bring the records
/// into the database buffer cache.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The table to issue the prereads against.</param>
/// <param name="keysStart">The start of key ranges to preread.</param>
/// <param name="keyStartLengths">The lengths of the start keys to preread.</param>
/// <param name="keysEnd">The end of key rangess to preread.</param>
/// <param name="keyEndLengths">The lengths of the end keys to preread.</param>
/// <param name="rangeIndex">The index of the first key range in the array to read.</param>
/// <param name="rangeCount">The maximum number of key ranges to preread.</param>
/// <param name="rangesPreread">Returns the number of keys actually preread.</param>
/// <param name="columnsPreread">List of column ids for long value columns to preread.</param>
/// <param name="grbit">Preread options. Used to specify the direction of the preread.</param>
/// <returns>An error or warning.</returns>
public int JetPrereadKeyRanges(
JET_SESID sesid,
JET_TABLEID tableid,
byte[][] keysStart,
int[] keyStartLengths,
byte[][] keysEnd,
int[] keyEndLengths,
int rangeIndex,
int rangeCount,
out int rangesPreread,
JET_COLUMNID[] columnsPreread,
PrereadIndexRangesGrbit grbit)
{
TraceFunctionCall("JetPrereadKeyRanges");
this.CheckSupportsWindows8Features("JetPrereadKeyRanges");
CheckDataSize(keysStart, rangeIndex, "rangeIndex", rangeCount, "rangeCount");
CheckDataSize(keyStartLengths, rangeIndex, "rangeIndex", rangeCount, "rangeCount");
CheckNotNull(keysStart, "keysStart");
if (keysEnd != null)
{
CheckNotNull(keyEndLengths, "keyEndLengths");
CheckDataSize(keysEnd, rangeIndex, "rangeIndex", rangeCount, "rangeCount");
}
if (keyEndLengths != null)
{
CheckNotNull(keysEnd, "keysEnd");
CheckDataSize(keyEndLengths, rangeIndex, "rangeIndex", rangeCount, "rangeCount");
}
grbit = grbit | PrereadIndexRangesGrbit.NormalizedKey;
using (var handles = new GCHandleCollection())
{
NATIVE_INDEX_COLUMN[] startColumn;
NATIVE_INDEX_COLUMN[] endColumn;
NATIVE_INDEX_RANGE[] ranges = new NATIVE_INDEX_RANGE[rangeCount];
for (int i = 0; i < rangeCount; i++)
{
startColumn = new NATIVE_INDEX_COLUMN[1];
startColumn[0].pvData = handles.Add(keysStart[i + rangeIndex]);
startColumn[0].cbData = (uint)keyStartLengths[i + rangeIndex];
ranges[i].rgStartColumns = handles.Add(startColumn);
ranges[i].cStartColumns = 1;
if (keysEnd != null)
{
endColumn = new NATIVE_INDEX_COLUMN[1];
endColumn[0].pvData = handles.Add(keysEnd[i + rangeIndex]);
endColumn[0].cbData = (uint)keyEndLengths[i + rangeIndex];
ranges[i].rgEndColumns = handles.Add(endColumn);
ranges[i].cEndColumns = 1;
}
}
if (columnsPreread != null)
{
var nativecolumnids = new uint[columnsPreread.Length];
for (int i = 0; i < columnsPreread.Length; i++)
{
nativecolumnids[i] = (uint)columnsPreread[i].Value;
}
return Err(NativeMethods.JetPrereadIndexRanges(sesid.Value, tableid.Value, ranges, (uint)rangeCount, out rangesPreread, nativecolumnids, (uint)columnsPreread.Length, checked((uint)grbit)));
}
else
{
return Err(NativeMethods.JetPrereadIndexRanges(sesid.Value, tableid.Value, ranges, (uint)rangeCount, out rangesPreread, null, (uint)0, checked((uint)grbit)));
}
}
}
/// <summary>
/// If the records with the specified key rangess are not in the buffer
/// cache, then start asynchronous reads to bring the records into the
/// database buffer cache.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The table to issue the prereads against.</param>
/// <param name="indexRanges">The key rangess to preread.</param>
/// <param name="rangeIndex">The index of the first key range in the array to read.</param>
/// <param name="rangeCount">The maximum number of key ranges to preread.</param>
/// <param name="rangesPreread">Returns the number of keys actually preread.</param>
/// <param name="columnsPreread">List of column ids for long value columns to preread.</param>
/// <param name="grbit">Preread options. Used to specify the direction of the preread.</param>
/// <returns>
/// An error if the call fails.
/// </returns>
public int JetPrereadIndexRanges(
JET_SESID sesid,
JET_TABLEID tableid,
JET_INDEX_RANGE[] indexRanges,
int rangeIndex,
int rangeCount,
out int rangesPreread,
JET_COLUMNID[] columnsPreread,
PrereadIndexRangesGrbit grbit)
{
TraceFunctionCall("JetPrereadIndexRanges");
this.CheckSupportsWindows8Features("JetPrereadIndexRanges");
CheckNotNull(indexRanges, "indexRanges");
CheckDataSize(indexRanges, rangeIndex, "rangeIndex", rangeCount, "rangeCount");
var handles = new GCHandleCollection();
try
{
NATIVE_INDEX_RANGE[] nativeRanges = new NATIVE_INDEX_RANGE[rangeCount];
for (int i = 0; i < rangeCount; i++)
{
nativeRanges[i] = indexRanges[i + rangeIndex].GetNativeIndexRange(ref handles);
}
if (columnsPreread != null)
{
var nativecolumnids = new uint[columnsPreread.Length];
for (int i = 0; i < columnsPreread.Length; i++)
{
nativecolumnids[i] = (uint)columnsPreread[i].Value;
}
return Err(NativeMethods.JetPrereadIndexRanges(sesid.Value, tableid.Value, nativeRanges, (uint)rangeCount, out rangesPreread, nativecolumnids, (uint)columnsPreread.Length, checked((uint)grbit)));
}
else
{
return Err(NativeMethods.JetPrereadIndexRanges(sesid.Value, tableid.Value, nativeRanges, (uint)rangeCount, out rangesPreread, null, (uint)0, checked((uint)grbit)));
}
}
finally
{
handles.Dispose();
}
}
/// <summary>
/// Gets the NATIVE_indexcolumn structure that represents the object.
/// </summary>
/// <param name="handles">GC handle collection to add any pinned handles.</param>
/// <returns>The NATIVE_indexcolumn structure.</returns>
internal NATIVE_INDEX_RANGE GetNativeIndexRange(ref GCHandleCollection handles)
{
NATIVE_INDEX_RANGE indexRange = new NATIVE_INDEX_RANGE();
NATIVE_INDEX_COLUMN[] nativeColumns;
if (this.startColumns != null)
{
nativeColumns = new NATIVE_INDEX_COLUMN[this.startColumns.Length];
for (int i = 0; i < this.startColumns.Length; i++)
{
nativeColumns[i] = this.startColumns[i].GetNativeIndexColumn(ref handles);
}
indexRange.rgStartColumns = handles.Add(nativeColumns);
indexRange.cStartColumns = (uint)this.startColumns.Length;
}
if (this.endColumns != null)
{
nativeColumns = new NATIVE_INDEX_COLUMN[this.endColumns.Length];
for (int i = 0; i < this.endColumns.Length; i++)
{
nativeColumns[i] = this.endColumns[i].GetNativeIndexColumn(ref handles);
}
indexRange.rgEndColumns = handles.Add(nativeColumns);
indexRange.cEndColumns = (uint)this.endColumns.Length;
}
return indexRange;
}