/// <summary>
/// Create an array of IndexSegment objects from the data in the current JET_INDEXLIST entry.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="indexlist">The indexlist to take the data from.</param>
/// <returns>An array of IndexSegment objects containing the information for the current index.</returns>
private static IndexSegment[] GetIndexSegmentsFromIndexlist(JET_SESID sesid, JET_INDEXLIST indexlist)
{
var numSegments = (int)Api.RetrieveColumnAsInt32(sesid, indexlist.tableid, indexlist.columnidcColumn);
Debug.Assert(numSegments > 0, "Index has zero index segments");
var segments = new IndexSegment[numSegments];
for (int i = 0; i < numSegments; ++i)
{
string columnName = Api.RetrieveColumnAsString(
sesid,
indexlist.tableid,
indexlist.columnidcolumnname,
NativeMethods.Encoding,
RetrieveColumnGrbit.None);
columnName = StringCache.TryToIntern(columnName);
var coltyp = (JET_coltyp)Api.RetrieveColumnAsInt32(sesid, indexlist.tableid, indexlist.columnidcoltyp);
var grbit =
(IndexKeyGrbit)Api.RetrieveColumnAsInt32(sesid, indexlist.tableid, indexlist.columnidgrbitColumn);
bool isAscending = IndexKeyGrbit.Ascending == grbit;
var cp = (JET_CP)Api.RetrieveColumnAsInt16(sesid, indexlist.tableid, indexlist.columnidCp);
bool isASCII = JET_CP.ASCII == cp;
segments[i] = new IndexSegment(columnName, coltyp, isAscending, isASCII);
if (i < numSegments - 1)
{
Api.JetMove(sesid, indexlist.tableid, JET_Move.Next, MoveGrbit.None);
}
}
return(segments);
}
/// <summary>
/// Create a ColumnInfo object from the data in the current JET_COLUMNLIST entry.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="columnlist">The columnlist to take the data from.</param>
/// <returns>A ColumnInfo object containing the information from that record.</returns>
private static ColumnInfo GetColumnInfoFromColumnlist(JET_SESID sesid, JET_COLUMNLIST columnlist)
{
string name = Api.RetrieveColumnAsString(
sesid,
columnlist.tableid,
columnlist.columnidcolumnname,
NativeMethods.Encoding,
RetrieveColumnGrbit.None);
name = StringCache.TryToIntern(name);
var columnidValue = (uint)Api.RetrieveColumnAsUInt32(sesid, columnlist.tableid, columnlist.columnidcolumnid);
var coltypValue = (uint)Api.RetrieveColumnAsUInt32(sesid, columnlist.tableid, columnlist.columnidcoltyp);
uint codepageValue = (ushort)Api.RetrieveColumnAsUInt16(sesid, columnlist.tableid, columnlist.columnidCp);
var maxLength = (uint)Api.RetrieveColumnAsUInt32(sesid, columnlist.tableid, columnlist.columnidcbMax);
byte[] defaultValue = Api.RetrieveColumn(sesid, columnlist.tableid, columnlist.columnidDefault);
var grbitValue = (uint)Api.RetrieveColumnAsUInt32(sesid, columnlist.tableid, columnlist.columnidgrbit);
return(new ColumnInfo(
name,
new JET_COLUMNID {
Value = columnidValue
},
(JET_coltyp)coltypValue,
(JET_CP)codepageValue,
checked ((int)maxLength),
defaultValue,
(ColumndefGrbit)grbitValue));
}
/// <summary>
/// Create an IndexInfo object from the data in the current JET_INDEXLIST entry.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="indexlist">The indexlist to take the data from.</param>
/// <returns>An IndexInfo object containing the information from that record.</returns>
private static IndexInfo GetIndexInfoFromIndexlist(JET_SESID sesid, JET_INDEXLIST indexlist)
{
string name = Api.RetrieveColumnAsString(
sesid, indexlist.tableid, indexlist.columnidindexname, NativeMethods.Encoding, RetrieveColumnGrbit.None);
name = StringCache.TryToIntern(name);
int lcid = (int)Api.RetrieveColumnAsInt16(sesid, indexlist.tableid, indexlist.columnidLangid);
var cultureInfo = new CultureInfo(lcid);
uint lcmapFlags = (uint)Api.RetrieveColumnAsUInt32(sesid, indexlist.tableid, indexlist.columnidLCMapFlags);
CompareOptions compareOptions = Conversions.CompareOptionsFromLCMapFlags(lcmapFlags);
uint grbit = (uint)Api.RetrieveColumnAsUInt32(sesid, indexlist.tableid, indexlist.columnidgrbitIndex);
int keys = (int)Api.RetrieveColumnAsInt32(sesid, indexlist.tableid, indexlist.columnidcKey);
int entries = (int)Api.RetrieveColumnAsInt32(sesid, indexlist.tableid, indexlist.columnidcEntry);
int pages = (int)Api.RetrieveColumnAsInt32(sesid, indexlist.tableid, indexlist.columnidcPage);
IndexSegment[] segments = GetIndexSegmentsFromIndexlist(sesid, indexlist);
return(new IndexInfo(
name,
cultureInfo,
compareOptions,
segments,
(CreateIndexGrbit)grbit,
keys,
entries,
pages));
}
/// <summary>
/// Create a ColumnInfo object from the data in the current JET_COLUMNLIST entry.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="columnlist">The columnlist to take the data from.</param>
/// <returns>A ColumnInfo object containing the information from that record.</returns>
private static ColumnInfo GetColumnInfoFromColumnlist(JET_SESID sesid, JET_COLUMNLIST columnlist)
{
// As of Sep 2015, JetGetColumnInfoW is only called for Win8+. Even though Unicode should have
// worked in Win7, it wasn't reliable until Win8.
Encoding encodingOfTextColumns = EsentVersion.SupportsWindows8Features ? Encoding.Unicode : LibraryHelpers.EncodingASCII;
string name = Api.RetrieveColumnAsString(
sesid,
columnlist.tableid,
columnlist.columnidcolumnname,
encodingOfTextColumns,
RetrieveColumnGrbit.None);
name = StringCache.TryToIntern(name);
var columnidValue = (uint)Api.RetrieveColumnAsUInt32(sesid, columnlist.tableid, columnlist.columnidcolumnid);
var coltypValue = (uint)Api.RetrieveColumnAsUInt32(sesid, columnlist.tableid, columnlist.columnidcoltyp);
uint codepageValue = (ushort)Api.RetrieveColumnAsUInt16(sesid, columnlist.tableid, columnlist.columnidCp);
var maxLength = (uint)Api.RetrieveColumnAsUInt32(sesid, columnlist.tableid, columnlist.columnidcbMax);
byte[] defaultValue = Api.RetrieveColumn(sesid, columnlist.tableid, columnlist.columnidDefault);
var grbitValue = (uint)Api.RetrieveColumnAsUInt32(sesid, columnlist.tableid, columnlist.columnidgrbit);
return(new ColumnInfo(
name,
new JET_COLUMNID {
Value = columnidValue
},
(JET_coltyp)coltypValue,
(JET_CP)codepageValue,
unchecked ((int)maxLength),
defaultValue,
(ColumndefGrbit)grbitValue));
}
/// <summary>
/// Given data retrieved from ESENT, decode the data and set the value in the ColumnValue object.
/// </summary>
/// <param name="value">An array of bytes.</param>
/// <param name="startIndex">The starting position within the bytes.</param>
/// <param name="count">The number of bytes to decode.</param>
/// <param name="err">The error returned from ESENT.</param>
protected override void GetValueFromBytes(byte[] value, int startIndex, int count, int err)
{
if (JET_wrn.ColumnNull == (JET_wrn)err)
{
this.Value = null;
}
else
{
this.Value = StringCache.GetString(value, startIndex, count);
}
}
/// <summary>
/// Gets the entry the cursor is currently positioned on.
/// </summary>
/// <returns>The entry the cursor is currently positioned on.</returns>
protected override string GetCurrent()
{
string name = Api.RetrieveColumnAsString(
this.Sesid,
this.TableidToEnumerate,
this.objectlist.columnidobjectname,
NativeMethods.Encoding,
RetrieveColumnGrbit.None);
return(StringCache.TryToIntern(name));
}
/// <summary>
/// Initializes a new instance of the <see cref="JET_COLUMNBASE"/> class.
/// </summary>
/// <param name="value">
/// The value.
/// </param>
internal JET_COLUMNBASE(NATIVE_COLUMNBASE value)
{
this.coltyp = (JET_coltyp)value.coltyp;
this.cp = (JET_CP)value.cp;
this.cbMax = checked ((int)value.cbMax);
this.grbit = (ColumndefGrbit)value.grbit;
this.columnid = new JET_COLUMNID {
Value = value.columnid
};
this.szBaseTableName = StringCache.TryToIntern(value.szBaseTableName);
this.szBaseColumnName = StringCache.TryToIntern(value.szBaseColumnName);
}
/// <summary>
/// Gets the entry the cursor is currently positioned on.
/// </summary>
/// <returns>The entry the cursor is currently positioned on.</returns>
protected override string GetCurrent()
{
// If we use the wide API (Vista+), then the temp table will be in UTF-16.
Encoding encodingOfTextColumns = EsentVersion.SupportsVistaFeatures ? Encoding.Unicode : LibraryHelpers.EncodingASCII;
string name = Api.RetrieveColumnAsString(
this.Sesid,
this.TableidToEnumerate,
this.objectlist.columnidobjectname,
encodingOfTextColumns,
RetrieveColumnGrbit.None);
return(StringCache.TryToIntern(name));
}
/// <summary>
/// Create an IndexInfo object from the data in the current JET_INDEXLIST entry.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="indexlist">The indexlist to take the data from.</param>
/// <returns>An IndexInfo object containing the information from that record.</returns>
private IndexInfo GetIndexInfoFromIndexlist(JET_SESID sesid, JET_INDEXLIST indexlist)
{
// If we use the wide API (Vista+), then the temp table will be in UTF-16.
Encoding encodingOfTextColumns = EsentVersion.SupportsVistaFeatures ? Encoding.Unicode : LibraryHelpers.EncodingASCII;
string name = Api.RetrieveColumnAsString(
sesid, indexlist.tableid, indexlist.columnidindexname, encodingOfTextColumns, RetrieveColumnGrbit.None);
name = StringCache.TryToIntern(name);
CultureInfo cultureInfo = null;
if (EsentVersion.SupportsWindows8Features)
{
string localeName;
this.GetIndexInfo(sesid, name, out localeName, Windows8IdxInfo.LocaleName);
cultureInfo = new CultureInfo(localeName);
}
else
{
#if !MANAGEDESENT_ON_CORECLR
// This probably won't work on platforms that don't support LCIDs. Newer environments have dropped
// LCIDs in favour of locale names. But currently JET_INDEXLIST doesn't expose columnidLocale.
int lcid = (int)Api.RetrieveColumnAsInt16(sesid, indexlist.tableid, indexlist.columnidLangid);
cultureInfo = LibraryHelpers.CreateCultureInfoByLcid(lcid);
#endif // !MANAGEDESENT_ON_CORECLR
}
uint lcmapFlags = (uint)Api.RetrieveColumnAsUInt32(sesid, indexlist.tableid, indexlist.columnidLCMapFlags);
CompareOptions compareOptions = Conversions.CompareOptionsFromLCMapFlags(lcmapFlags);
uint grbit = (uint)Api.RetrieveColumnAsUInt32(sesid, indexlist.tableid, indexlist.columnidgrbitIndex);
int keys = (int)Api.RetrieveColumnAsInt32(sesid, indexlist.tableid, indexlist.columnidcKey);
int entries = (int)Api.RetrieveColumnAsInt32(sesid, indexlist.tableid, indexlist.columnidcEntry);
int pages = (int)Api.RetrieveColumnAsInt32(sesid, indexlist.tableid, indexlist.columnidcPage);
IndexSegment[] segments = GetIndexSegmentsFromIndexlist(sesid, indexlist);
return(new IndexInfo(
name,
cultureInfo,
compareOptions,
segments,
(CreateIndexGrbit)grbit,
keys,
entries,
pages));
}
/// <summary>
/// Creates a dictionary which maps column names to their column IDs.
/// </summary>
/// <param name="sesid">The sesid to use.</param>
/// <param name="tableid">The table to retrieve the information for.</param>
/// <returns>A dictionary mapping column names to column IDs.</returns>
public static IDictionary <string, JET_COLUMNID> GetColumnDictionary(JET_SESID sesid, JET_TABLEID tableid)
{
JET_COLUMNLIST columnlist;
JetGetTableColumnInfo(sesid, tableid, string.Empty, out columnlist);
// As of Sep 2015, JetGetColumnInfoW is only called for Win8+. Even though Unicode should have
// worked in Win7, it wasn't reliable until Win8.
Encoding encodingOfTextColumns = EsentVersion.SupportsWindows8Features ? Encoding.Unicode : LibraryHelpers.EncodingASCII;
try
{
// esent treats column names as case-insensitive, so we want the dictionary to be case insensitive as well
var dict = new Dictionary <string, JET_COLUMNID>(
columnlist.cRecord, StringComparer.OrdinalIgnoreCase);
if (columnlist.cRecord > 0)
{
if (Api.TryMoveFirst(sesid, columnlist.tableid))
{
do
{
string name = RetrieveColumnAsString(
sesid,
columnlist.tableid,
columnlist.columnidcolumnname,
encodingOfTextColumns,
RetrieveColumnGrbit.None);
name = StringCache.TryToIntern(name);
var columnidValue =
(uint)RetrieveColumnAsUInt32(sesid, columnlist.tableid, columnlist.columnidcolumnid);
var columnid = new JET_COLUMNID {
Value = columnidValue
};
dict.Add(name, columnid);
}while (TryMoveNext(sesid, columnlist.tableid));
}
}
return(dict);
}
finally
{
// Close the temporary table used to return the results
JetCloseTable(sesid, columnlist.tableid);
}
}
/// <summary>
/// Creates a dictionary which maps column names to their column IDs.
/// </summary>
/// <param name="sesid">The sesid to use.</param>
/// <param name="tableid">The table to retrieve the information for.</param>
/// <returns>A dictionary mapping column names to column IDs.</returns>
public static IDictionary <string, JET_COLUMNID> GetColumnDictionary(JET_SESID sesid, JET_TABLEID tableid)
{
JET_COLUMNLIST columnlist;
JetGetTableColumnInfo(sesid, tableid, string.Empty, out columnlist);
try
{
// esent treats column names as case-insensitive, so we want the dictionary to be case insensitive as well
var dict = new Dictionary <string, JET_COLUMNID>(
columnlist.cRecord, StringComparer.OrdinalIgnoreCase);
if (columnlist.cRecord > 0)
{
if (Api.TryMoveFirst(sesid, columnlist.tableid))
{
do
{
string name = RetrieveColumnAsString(
sesid,
columnlist.tableid,
columnlist.columnidcolumnname,
NativeMethods.Encoding,
RetrieveColumnGrbit.None);
name = StringCache.TryToIntern(name);
var columnidValue =
(uint)RetrieveColumnAsUInt32(sesid, columnlist.tableid, columnlist.columnidcolumnid);
var columnid = new JET_COLUMNID {
Value = columnidValue
};
dict.Add(name, columnid);
}while (TryMoveNext(sesid, columnlist.tableid));
}
}
return(dict);
}
finally
{
// Close the temporary table used to return the results
JetCloseTable(sesid, columnlist.tableid);
}
}
/// <summary>
/// Create an array of IndexSegment objects from the data in the current JET_INDEXLIST entry.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="indexlist">The indexlist to take the data from.</param>
/// <returns>An array of IndexSegment objects containing the information for the current index.</returns>
private static IndexSegment[] GetIndexSegmentsFromIndexlist(JET_SESID sesid, JET_INDEXLIST indexlist)
{
var numSegments = (int)Api.RetrieveColumnAsInt32(sesid, indexlist.tableid, indexlist.columnidcColumn);
Debug.Assert(numSegments > 0, "Index has zero index segments");
// If we use the wide API (Vista+), then the temp table will be in UTF-16.
Encoding encodingOfTextColumns = EsentVersion.SupportsVistaFeatures ? Encoding.Unicode : LibraryHelpers.EncodingASCII;
var segments = new IndexSegment[numSegments];
for (int i = 0; i < numSegments; ++i)
{
string columnName = Api.RetrieveColumnAsString(
sesid,
indexlist.tableid,
indexlist.columnidcolumnname,
encodingOfTextColumns,
RetrieveColumnGrbit.None);
columnName = StringCache.TryToIntern(columnName);
var coltyp = (JET_coltyp)Api.RetrieveColumnAsInt32(sesid, indexlist.tableid, indexlist.columnidcoltyp);
var grbit =
(IndexKeyGrbit)Api.RetrieveColumnAsInt32(sesid, indexlist.tableid, indexlist.columnidgrbitColumn);
bool isAscending = IndexKeyGrbit.Ascending == grbit;
var cp = (JET_CP)Api.RetrieveColumnAsInt16(sesid, indexlist.tableid, indexlist.columnidCp);
bool isASCII = JET_CP.ASCII == cp;
segments[i] = new IndexSegment(columnName, coltyp, isAscending, isASCII);
if (i < numSegments - 1)
{
Api.JetMove(sesid, indexlist.tableid, JET_Move.Next, MoveGrbit.None);
}
}
return(segments);
}