public void VerifyUpdateFromNativeRetrievecolumnSetsCbactual()
{
var setcolumn = new JET_RETRIEVECOLUMN();
var native = new NATIVE_RETRIEVECOLUMN { cbActual = 0x100 };
setcolumn.UpdateFromNativeRetrievecolumn(native);
Assert.AreEqual(0x100, setcolumn.cbActual);
}
public void VerifyCheckThrowsExceptionWhenPvDataIsNull()
{
var setcolumn = new JET_RETRIEVECOLUMN
{
cbData = 1,
};
setcolumn.CheckDataSize();
}
public void VerifyCheckThrowsExceptionWhenCbDataIsTooLong()
{
var setcolumn = new JET_RETRIEVECOLUMN
{
cbData = 100,
pvData = new byte[9],
};
setcolumn.CheckDataSize();
}
public void VerifyCheckThrowsExceptionWhenCbDataIsNegative()
{
var setcolumn = new JET_RETRIEVECOLUMN
{
cbData = -1,
pvData = new byte[1],
};
setcolumn.CheckDataSize();
}
public void VerifyCheckThrowsExceptionWhenIbCbDataIsTooLong()
{
var setcolumn = new JET_RETRIEVECOLUMN
{
ibData = 8,
cbData = 3,
pvData = new byte[10],
};
setcolumn.CheckDataSize();
}
public void Setup()
{
this.managed = new JET_RETRIEVECOLUMN
{
cbData = 1,
columnid = new JET_COLUMNID { Value = 2 },
grbit = RetrieveColumnGrbit.RetrieveCopy,
ibLongValue = 3,
itagSequence = 4,
};
this.native = this.managed.GetNativeRetrievecolumn();
}
public void HowDoIDealWithMultivalues()
{
JET_SESID sesid = this.testSession;
JET_DBID dbid = this.testDbid;
JET_TABLEID tableid;
JET_COLUMNDEF columndef = new JET_COLUMNDEF();
JET_COLUMNID tagColumn;
Api.JetCreateTable(sesid, dbid, "table", 0, 100, out tableid);
// Create the column. Any column can be multivalued. Using
// ColumndefGrbit controls how the column is indexed.
columndef.coltyp = JET_coltyp.LongText;
columndef.cp = JET_CP.Unicode;
columndef.grbit = ColumndefGrbit.ColumnMultiValued;
Api.JetAddColumn(sesid, tableid, "tags", columndef, null, 0, out tagColumn);
// Create the index. There will be one entry in the index for each
// instance of the multivalued column.
const string IndexKey = "+tags\0\0";
Api.JetCreateIndex(sesid, tableid, "tagsindex", CreateIndexGrbit.None, IndexKey, IndexKey.Length, 100);
Api.JetBeginTransaction(sesid);
// Now insert a record. An ESENT column can have multiple instances (multivalues)
// inside the same record. Each multivalue is identified by an itag, the first itag
// in a sequence is 1.
Api.JetPrepareUpdate(sesid, tableid, JET_prep.Insert);
// With no JET_SETINFO specified, itag 1 will be set.
byte[] data = Encoding.Unicode.GetBytes("foo");
Api.JetSetColumn(sesid, tableid, tagColumn, data, data.Length, SetColumnGrbit.None, null);
// Set a column with a setinfo. The itagSequence in the setinfo will be 0, which
// means the value will be added to the collection of values, i.e. the column will
// have two instances, "foo" and "bar".
JET_SETINFO setinfo = new JET_SETINFO();
data = Encoding.Unicode.GetBytes("bar");
Api.JetSetColumn(sesid, tableid, tagColumn, data, data.Length, SetColumnGrbit.None, setinfo);
// Add a third instance, explicitly setting the itagSequence
data = Encoding.Unicode.GetBytes("baz");
setinfo.itagSequence = 4;
Api.JetSetColumn(sesid, tableid, tagColumn, data, data.Length, SetColumnGrbit.None, setinfo);
// Add a duplicate value, checking for uniqueness
data = Encoding.Unicode.GetBytes("foo");
setinfo.itagSequence = 0;
try
{
Api.JetSetColumn(sesid, tableid, tagColumn, data, data.Length, SetColumnGrbit.UniqueMultiValues, setinfo);
Assert.Fail("Expected an EsentErrorException");
}
catch (EsentErrorException ex)
{
Assert.AreEqual(JET_err.MultiValuedDuplicate, ex.Error);
}
Api.JetUpdate(sesid, tableid);
// Find the record. We can seek for any column instance.
Api.JetSetCurrentIndex(sesid, tableid, "tagsindex");
Api.MakeKey(sesid, tableid, "bar", Encoding.Unicode, MakeKeyGrbit.NewKey);
Assert.IsTrue(Api.TrySeek(sesid, tableid, SeekGrbit.SeekEQ));
// Retrieve the number of column instances. This can be done with JetRetrieveColumns by setting
// itagSequence to 0.
JET_RETRIEVECOLUMN retrievecolumn = new JET_RETRIEVECOLUMN();
retrievecolumn.columnid = tagColumn;
retrievecolumn.itagSequence = 0;
Api.JetRetrieveColumns(sesid, tableid, new[] { retrievecolumn }, 1);
Console.WriteLine("{0}", retrievecolumn.itagSequence);
Assert.AreEqual(3, retrievecolumn.itagSequence);
// Retrieve all the columns
for (int itag = 1; itag <= retrievecolumn.itagSequence; ++itag)
{
JET_RETINFO retinfo = new JET_RETINFO { itagSequence = itag };
string s = Encoding.Unicode.GetString(Api.RetrieveColumn(sesid, tableid, tagColumn, RetrieveColumnGrbit.None, retinfo));
Console.WriteLine("{0}: {1}", itag, s);
}
// Update the record
Api.JetPrepareUpdate(sesid, tableid, JET_prep.Replace);
// With no JET_SETINFO specified, itag 1 will be set, overwriting the existing value.
data = Encoding.Unicode.GetBytes("qux");
Api.JetSetColumn(sesid, tableid, tagColumn, data, data.Length, SetColumnGrbit.None, null);
// Set an instance to null to delete it.
setinfo.itagSequence = 2;
Api.JetSetColumn(sesid, tableid, tagColumn, null, 0, SetColumnGrbit.None, setinfo);
// Removing itag 2 moved the other itags down (i.e. itag 3 became itag 2).
// Overwrite itag 2.
data = Encoding.Unicode.GetBytes("xyzzy");
setinfo.itagSequence = 2;
Api.JetSetColumn(sesid, tableid, tagColumn, data, data.Length, SetColumnGrbit.None, setinfo);
// Now add a new instance by setting itag 0. This instance will go at the end.
data = Encoding.Unicode.GetBytes("flob");
setinfo.itagSequence = 0;
Api.JetSetColumn(sesid, tableid, tagColumn, data, data.Length, SetColumnGrbit.None, setinfo);
Api.JetUpdate(sesid, tableid);
// Retrieve the number of column instances again.
retrievecolumn.itagSequence = 0;
Api.JetRetrieveColumns(sesid, tableid, new[] { retrievecolumn }, 1);
// Retrieve all the columns
for (int itag = 1; itag <= retrievecolumn.itagSequence; ++itag)
{
JET_RETINFO retinfo = new JET_RETINFO { itagSequence = itag };
string s = Encoding.Unicode.GetString(Api.RetrieveColumn(sesid, tableid, tagColumn, RetrieveColumnGrbit.None, retinfo));
Console.WriteLine("{0}: {1}", itag, s);
}
Api.JetCommitTransaction(sesid, CommitTransactionGrbit.LazyFlush);
}
public void VerifyUpdateFromNativeRetrievecolumnSetsColumnidNextTagged()
{
var setcolumn = new JET_RETRIEVECOLUMN();
var native = new NATIVE_RETRIEVECOLUMN { columnidNextTagged = 0x20 };
setcolumn.UpdateFromNativeRetrievecolumn(native);
var expected = new JET_COLUMNID { Value = 0x20 };
Assert.AreEqual(expected, setcolumn.columnidNextTagged);
}
public void VerifyUpdateFromNativeRetrievecolumnSetsErr()
{
var setcolumn = new JET_RETRIEVECOLUMN();
var native = new NATIVE_RETRIEVECOLUMN { err = 1004 };
setcolumn.UpdateFromNativeRetrievecolumn(native);
Assert.AreEqual(JET_wrn.ColumnNull, setcolumn.err);
}
/// <summary>
/// Retrieves multiple column values from the current record in a
/// single operation. An array of JET_RETRIEVECOLUMN structures is
/// used to describe the set of column values to be retrieved, and
/// to describe output buffers for each column value to be retrieved.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to retrieve the data from.</param>
/// <param name="retrievecolumns">
/// An array of one or more <see cref="JET_RETRIEVECOLUMN"/> objects
/// describing the data to be retrieved.
/// </param>
/// <param name="numColumns">
/// The number of entries in the columns array.
/// </param>
/// <returns>
/// If any column retrieved is truncated due to an insufficient
/// length buffer, then the API will return
/// <see cref="JET_wrn.BufferTruncated"/>. However other errors
/// JET_wrnColumnNull are returned only in the error field of
/// the <see cref="JET_RETRIEVECOLUMN"/> object.
/// </returns>
public static JET_wrn JetRetrieveColumns(JET_SESID sesid, JET_TABLEID tableid, JET_RETRIEVECOLUMN[] retrievecolumns, int numColumns)
{
if (null == retrievecolumns)
{
throw new ArgumentNullException("retrievecolumns");
}
if (numColumns < 0 || numColumns > retrievecolumns.Length)
{
throw new ArgumentOutOfRangeException("numColumns", numColumns, "cannot be negative or greater than retrievecolumns.Length");
}
unsafe
{
NATIVE_RETRIEVECOLUMN* nativeretrievecolumns = stackalloc NATIVE_RETRIEVECOLUMN[numColumns];
int err = Api.PinColumnsAndRetrieve(sesid, tableid, nativeretrievecolumns, retrievecolumns, numColumns, 0);
for (int i = 0; i < numColumns; ++i)
{
retrievecolumns[i].UpdateFromNativeRetrievecolumn(ref nativeretrievecolumns[i]);
}
return Api.Check(err);
}
}
/// <summary>
/// Retrieves multiple column values from the current record in a
/// single operation. An array of JET_RETRIEVECOLUMN structures is
/// used to describe the set of column values to be retrieved, and
/// to describe output buffers for each column value to be retrieved.
/// </summary>
/// <param name="sesid">The session to use.</param>
/// <param name="tableid">The cursor to retrieve the data from.</param>
/// <param name="columns">
/// An array of one or more <see cref="JET_RETRIEVECOLUMN"/> objects
/// describing the data to be retrieved.
/// </param>
/// <param name="numColumns">
/// The number of entries in the columns array.
/// </param>
/// <returns>
/// If any column retrieved is truncated due to an insufficient
/// length buffer, then the API will return
/// <see cref="JET_wrn.BufferTruncated"/>. However other errors
/// JET_wrnColumnNull are returned only in the error field of
/// the <see cref="JET_RETRIEVECOLUMN"/> object.
/// </returns>
public static JET_wrn JetRetrieveColumns(JET_SESID sesid, JET_TABLEID tableid, JET_RETRIEVECOLUMN[] columns, int numColumns)
{
throw new NotImplementedException("JetRetrieveColumns");
}
public void JetRetrievecolumnToString()
{
var value = new JET_RETRIEVECOLUMN { columnid = new JET_COLUMNID { Value = 27 } };
Assert.AreEqual("JET_RETRIEVECOLUMN(0x1b)", value.ToString());
}
public void VerifyUpdateFromNativeRetrievecolumnSetsItagSequence()
{
var setcolumn = new JET_RETRIEVECOLUMN();
var native = new NATIVE_RETRIEVECOLUMN { itagSequence = 7 };
setcolumn.UpdateFromNativeRetrievecolumn(ref native);
Assert.AreEqual(7, setcolumn.itagSequence);
}