/// <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="indexRanges">The key ranges 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><c>true</c> if some preread done, <c>false</c> otherwise.</returns>
public static bool JetTryPrereadIndexRanges(
JET_SESID sesid,
JET_TABLEID tableid,
JET_INDEX_RANGE[] indexRanges,
int rangeIndex,
int rangeCount,
out int rangesPreread,
JET_COLUMNID[] columnsPreread,
PrereadIndexRangesGrbit grbit)
{
JET_err err = (JET_err)Api.Impl.JetPrereadIndexRanges(sesid, tableid, indexRanges, rangeIndex, rangeCount, out rangesPreread, columnsPreread, grbit);
return err >= JET_err.Success;
}
/// <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>
/// 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="indexRanges">The key ranges 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>
public static void JetPrereadIndexRanges(
JET_SESID sesid,
JET_TABLEID tableid,
JET_INDEX_RANGE[] indexRanges,
int rangeIndex,
int rangeCount,
out int rangesPreread,
JET_COLUMNID[] columnsPreread,
PrereadIndexRangesGrbit grbit)
{
Api.Check(Api.Impl.JetPrereadIndexRanges(sesid, tableid, indexRanges, rangeIndex, rangeCount, out rangesPreread, columnsPreread, grbit));
}
