public IEnumerable <DBRow> GetIndexInfo(string tableName, string indexName)
{
IEnumerable <ColSpec> tableDef = GetIndexTableDef(tableName, indexName);
JET_INDEXLIST indexList;
Esent.JetGetIndexInfo(m_sesid, m_dbid, tableName, indexName, out indexList, JET_IdxInfo.List);
var columnsByName = new Dictionary <string, int>();
int i = 0;
foreach (ColSpec column in tableDef)
{
columnsByName.Add(column.Name, i++);
}
Esent.JetMove(m_sesid, indexList.tableid, JET_Move.First, MoveGrbit.None);
i = 0;
do
{
var row = new List <object>();
foreach (ColSpec column in tableDef)
{
row.Add(column.Retriever(m_sesid, indexList.tableid, column.ColumnId));
}
yield return(new DBRow(columnsByName, row, i++));
}while (Esent.TryMoveNext(m_sesid, indexList.tableid));
Esent.JetCloseTable(m_sesid, indexList.tableid);
}
} // GetRows
public IEnumerable <string> GetIndexes(string tableName)
{
foreach (IndexInfo info in Esent.GetTableIndexes(m_sesid, m_dbid, tableName))
{
yield return(info.Name);
}
}
public void Init(bool recoveryEnabled)
{
int pageSize;
Esent.JetGetDatabaseFileInfo(m_filename, out pageSize, JET_DbInfo.PageSize);
string dir = Path.GetDirectoryName(m_filename) + Path.DirectorySeparatorChar;
Esent.JetSetSystemParameter(JET_INSTANCE.Nil, JET_SESID.Nil, JET_param.DatabasePageSize, pageSize, null);
Esent.JetSetSystemParameter(JET_INSTANCE.Nil, JET_SESID.Nil, JET_param.LogFilePath, 0, dir);
Esent.JetSetSystemParameter(JET_INSTANCE.Nil, JET_SESID.Nil, JET_param.SystemPath, 0, dir);
// Put the temp DB in our working directory.
Esent.JetSetSystemParameter(JET_INSTANCE.Nil, JET_SESID.Nil, JET_param.TempPath, 0, Directory.GetCurrentDirectory() + Path.DirectorySeparatorChar);
// Set recovery option.
Esent.JetSetSystemParameter(JET_INSTANCE.Nil, JET_SESID.Nil, JET_param.Recovery, 0, recoveryEnabled ? "On" : "Off");
m_jetInstance = new Instance("ESEVIEW");
m_jetInstance.Init();
m_sesid = new Session(m_jetInstance);
Esent.JetAttachDatabase(m_sesid, m_filename, recoveryEnabled ? AttachDatabaseGrbit.None : AttachDatabaseGrbit.ReadOnly);
Esent.JetOpenDatabase(m_sesid, m_filename, null, out m_dbid, OpenDatabaseGrbit.ReadOnly);
}
public IEnumerable <List <object> > GetRows(string tableName, string indexName = null, int startRow = 0, int rowCount = -1)
{
if (!m_tableDefs.ContainsKey(tableName))
{
LoadTableDef(tableName);
}
using (var table = new Table(m_sesid, m_dbid, tableName, OpenTableGrbit.ReadOnly)) {
var colspec = new List <KeyValuePair <string, Type> >();
try {
Esent.JetSetCurrentIndex2(m_sesid, table, indexName, SetCurrentIndexGrbit.MoveFirst);
if (startRow != 0)
{
Esent.JetMove(m_sesid, table, startRow, MoveGrbit.None);
}
}
catch (EsentNoCurrentRecordException) {
// Return an empty set.
yield break;
}
int rowNumber = 0;
do
{
var values = new List <object>();
object value = null;
foreach (var column in m_tableDefs[tableName])
{
try {
value = column.Retriever(m_sesid, table, column.ColumnId);
}
catch (Microsoft.Isam.Esent.Interop.EsentNoCurrentRecordException) {
// If we get this on row 0, it means there are no rows.
if (rowNumber == 0)
{
yield break;
}
else
{
throw;
}
}
values.Add(value);
}
yield return(values);
rowNumber++;
if (rowNumber == rowCount)
{
yield break;
}
}while (Esent.TryMoveNext(m_sesid, table));
}
} // GetRows
public void Close()
{
if ((m_sesid != null) && (m_sesid.JetSesid != JET_SESID.Nil))
{
if (!m_dbid.Equals(JET_DBID.Nil))
{
Esent.JetCloseDatabase(m_sesid, m_dbid, CloseDatabaseGrbit.None);
}
m_sesid.End();
}
if ((m_jetInstance != null) && !m_jetInstance.Equals(JET_INSTANCE.Nil))
{
m_jetInstance.Close();
}
}
public int GetRowCount(string tableName, string indexName = null)
{
if (string.IsNullOrEmpty(tableName))
{
return(0);
}
using (var table = new Table(m_sesid, m_dbid, tableName, OpenTableGrbit.ReadOnly)) {
if (!string.IsNullOrEmpty(indexName))
{
// This is needed because an index can be over a nullable column and exclude
// the nulls, resulting in fewer records than when not using the index.
Esent.JetSetCurrentIndex2(m_sesid, table, indexName, SetCurrentIndexGrbit.MoveFirst);
}
int numRecords;
Esent.JetIndexRecordCount(m_sesid, table, out numRecords, 0);
return(numRecords);
}
}
private IEnumerable <ColSpec> GetIndexTableDef(string tableName, string indexName)
{
JET_INDEXLIST indexList;
Esent.JetGetIndexInfo(m_sesid, m_dbid, tableName, indexName, out indexList, JET_IdxInfo.List);
// Unfortunately, Esent.GetTableColumns doesn't work on the temporary table returned by
// JetGetIndexInfo, but the JET_INDEXLIST and the documentation have all the
// information we need.
var tableDef = new ColSpec[] {
new ColSpec
{
Name = "Columns",
Type = typeof(Int32?),
ColumnId = indexList.columnidcColumn
},
new ColSpec
{
Name = "Entries",
Type = typeof(Int32?),
ColumnId = indexList.columnidcEntry
},
new ColSpec
{
Name = "UniqueKeys",
Type = typeof(Int32?),
ColumnId = indexList.columnidcKey
},
new ColSpec {
Name = "Coltyp",
Type = typeof(Int32?),
ColumnId = indexList.columnidcoltyp
},
new ColSpec {
Name = "ColumnId",
Type = typeof(Int32?),
ColumnId = indexList.columnidcolumnid
},
new ColSpec {
Name = "ColumnName",
Type = typeof(string),
ColumnId = indexList.columnidcolumnname
},
new ColSpec {
Name = "CodePage",
Type = typeof(Int16?),
ColumnId = indexList.columnidCp
},
new ColSpec {
Name = "NumPages",
Type = typeof(Int32?),
ColumnId = indexList.columnidcPage
},
new ColSpec {
Name = "grbitColumn",
Type = typeof(Int32?),
ColumnId = indexList.columnidgrbitColumn
},
new ColSpec {
Name = "grbitIndex",
Type = typeof(Int32?),
ColumnId = indexList.columnidgrbitIndex
},
new ColSpec {
Name = "iColumn",
Type = typeof(Int32?),
ColumnId = indexList.columnidiColumn
},
new ColSpec {
Name = "IndexName",
Type = typeof(string),
ColumnId = indexList.columnidindexname
},
new ColSpec {
Name = "LangId",
Type = typeof(Int16?),
ColumnId = indexList.columnidLangid
},
new ColSpec {
Name = "LCMapFlags",
Type = typeof(Int32?),
ColumnId = indexList.columnidLCMapFlags
}
};
for (int i = 0, n = tableDef.Length; i < n; i++)
{
tableDef[i].Retriever = ColumnRetrievers.ForType(tableDef[i].Type);
}
Esent.JetCloseTable(m_sesid, indexList.tableid);
return(tableDef);
}
private List <ColSpec> GetTableDef(JET_TABLEID table)
{
var columns = new List <ColumnInfo>(Esent.GetTableColumns(m_sesid, table));
var tableDef = new List <ColSpec>();
foreach (var column in columns)
{
var colspec = new ColSpec();
colspec.Name = column.Name;
colspec.ColumnId = column.Columnid;
colspec.Retriever = null;
switch (column.Coltyp)
{
case JET_coltyp.Text:
case JET_coltyp.LongText:
colspec.Type = typeof(string);
break;
case JET_coltyp.Long:
colspec.Type = typeof(int?);
break;
case JET_coltyp.Short:
colspec.Type = typeof(short?);
break;
case JET_coltyp.UnsignedByte:
colspec.Type = typeof(byte?);
break;
case JET_coltyp.Bit:
colspec.Type = typeof(bool?);
break;
case JET_coltyp.DateTime:
colspec.Type = typeof(DateTime?);
break;
case JET_coltyp.IEEEDouble:
colspec.Type = typeof(double?);
break;
case JET_coltyp.IEEESingle:
colspec.Type = typeof(float?);
break;
case JET_coltyp.Binary:
case JET_coltyp.LongBinary:
colspec.Retriever = (s, t, c) =>
{
byte[] value = Esent.RetrieveColumn(s, t, c);
if (value != null)
{
return(Convert.ToBase64String(value));
}
else
{
return(value);
}
};
colspec.Type = typeof(string);
break;
case VistaColtyp.UnsignedLong:
colspec.Type = typeof(UInt32?);
break;
case VistaColtyp.LongLong:
colspec.Type = typeof(Int64?);
break;
case VistaColtyp.GUID:
colspec.Type = typeof(Guid?);
break;
case VistaColtyp.UnsignedShort:
colspec.Type = typeof(UInt16?);
break;
default:
colspec.Retriever = (s, t, c) => "ERROR: unhandled type " + Enum.GetName(typeof(JET_coltyp), column.Coltyp) + "(" + (int)column.Coltyp + ")";
colspec.Type = typeof(string);
break;
}
if (colspec.Retriever == null)
{
colspec.Retriever = ColumnRetrievers.ForType(colspec.Type);
}
tableDef.Add(colspec);
}
return(tableDef);
}
/// <summary>
/// Constructs a search key that may then be used by <see cref="JetSeek"/>
/// and <see cref="JetSetIndexRange"/>.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to create the key on.</param>
/// <param name="data">Column data for the current key column of the current index.</param>
/// <param name="grbit">Key options.</param>
public static void MakeKey(JET_SESID sesid, JET_TABLEID tableid, bool data, MakeKeyGrbit grbit)
{
byte b = data ? (byte)0xff : (byte)0x0;
Api.MakeKey(sesid, tableid, b, grbit);
}
/// <summary>
/// Constructs a search key that may then be used by <see cref="JetSeek"/>
/// and <see cref="JetSetIndexRange"/>.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to create the key on.</param>
/// <param name="data">Column data for the current key column of the current index.</param>
/// <param name="grbit">Key options.</param>
public static void MakeKey(JET_SESID sesid, JET_TABLEID tableid, DateTime data, MakeKeyGrbit grbit)
{
Api.MakeKey(sesid, tableid, data.ToOADate(), grbit);
}
