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public static JetGetIndexInfo ( JET_SESID sesid, JET_DBID dbid, string tablename, string ignored, |
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| sesid | JET_SESID | The session to use. |
| dbid | JET_DBID | The database to use. |
| tablename | string | The name of the table to retrieve index information about. |
| ignored | string | This parameter is ignored. |
| indexlist | Filled in with information about indexes on the table. | |
| return | void | |
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);
}
public static void JetGetIndexInfo(
JET_SESID sesid,
JET_DBID dbid,
string tablename,
string ignored,
out JET_INDEXLIST indexlist)
{
Api.JetGetIndexInfo(sesid, dbid, tablename, ignored, out indexlist, JET_IdxInfo.List);
}
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);
}