public void FreeSlot_Insert()
{
using (var e = new LiteEngine())
{
e.BeginTrans();
// get transaction/snapshot "col1"
var t = e.GetMonitor().GetTransaction(false, out var isNew);
var s = t.CreateSnapshot(LockMode.Write, "col1", true);
e.Insert("col1", new BsonDocument[] { new BsonDocument {
["n"] = new byte[200]
} }, BsonAutoId.Int32);
// get pages
var colPage = s.CollectionPage;
var dataPage = s.LocalPages.FirstOrDefault(x => x.PageType == PageType.Data);
var indexPage = s.LocalPages.FirstOrDefault(x => x.PageType == PageType.Index);
// test dataPage free space
dataPage.FreeBytes.Should().Be(7928);
// page should be in Slot #0 (7344 - 8160 free bytes)
colPage.FreeDataPageList.Should().Equal(dataPage.PageID, uint.MaxValue, uint.MaxValue, uint.MaxValue, uint.MaxValue);
// adding 1 more document into same page
e.Insert("col1", new BsonDocument[] { new BsonDocument {
["n"] = new byte[600]
} }, BsonAutoId.Int32);
dataPage.FreeBytes.Should().Be(7296);
// page should me moved into Slot #1 (6120 - 7343 free bytes)
colPage.FreeDataPageList.Should().Equal(uint.MaxValue, dataPage.PageID, uint.MaxValue, uint.MaxValue, uint.MaxValue);
// adding 1 big document to move this page into last page
e.Insert("col1", new BsonDocument[] { new BsonDocument {
["n"] = new byte[6000]
} }, BsonAutoId.Int32);
dataPage.FreeBytes.Should().Be(1264);
// now this page should me moved into last Slot (#4) - next document will use another data page (even a very small document)
colPage.FreeDataPageList.Should().Equal(uint.MaxValue, uint.MaxValue, uint.MaxValue, uint.MaxValue, dataPage.PageID);
// adding a very small document to test adding new page
e.Insert("col1", new BsonDocument[] { new BsonDocument {
["n"] = new byte[10]
} }, BsonAutoId.Int32);
// no changes in dataPage... but new page as created
dataPage.FreeBytes.Should().Be(1264);
var dataPage2 = s.LocalPages.FirstOrDefault(x => x.PageType == PageType.Data && x.PageID != dataPage.PageID);
dataPage2.FreeBytes.Should().Be(8118);
// test slots (#0 for dataPage2 and #4 for dataPage1)
colPage.FreeDataPageList.Should().Equal(dataPage2.PageID, uint.MaxValue, uint.MaxValue, uint.MaxValue, dataPage.PageID);
// add another big document into dataPage2 do put both pages in same free Slot (#4)
e.Insert("col1", new BsonDocument[] { new BsonDocument {
["n"] = new byte[7000]
} }, BsonAutoId.Int32);
// now, both pages are linked in same slot #4 (starts with new dataPage2)
colPage.FreeDataPageList.Should().Equal(uint.MaxValue, uint.MaxValue, uint.MaxValue, uint.MaxValue, dataPage2.PageID);
// dataPage2 link into dataPage1
dataPage2.NextPageID.Should().Be(dataPage.PageID);
dataPage.PrevPageID.Should().Be(dataPage2.PageID);
// and both start/end points to null
dataPage2.PrevPageID.Should().Be(uint.MaxValue);
dataPage.NextPageID.Should().Be(uint.MaxValue);
// do ColID tests
dataPage.ColID.Should().Be(colPage.PageID);
dataPage2.ColID.Should().Be(colPage.PageID);
indexPage.ColID.Should().Be(colPage.PageID);
}
}
public void FreeSlot_Delete()
{
using (var e = new LiteEngine())
{
e.BeginTrans();
// get transaction/snapshot "col1"
var t = e.GetMonitor().GetTransaction(false, out var isNew);
var s = t.CreateSnapshot(LockMode.Write, "col1", true);
// first page
e.Insert("col1", new BsonDocument[] { new BsonDocument {
["_id"] = 1, ["n"] = new byte[2000]
} }, BsonAutoId.Int32);
e.Insert("col1", new BsonDocument[] { new BsonDocument {
["_id"] = 2, ["n"] = new byte[2000]
} }, BsonAutoId.Int32);
e.Insert("col1", new BsonDocument[] { new BsonDocument {
["_id"] = 3, ["n"] = new byte[2000]
} }, BsonAutoId.Int32);
// second page
e.Insert("col1", new BsonDocument[] { new BsonDocument {
["_id"] = 4, ["n"] = new byte[2000]
} }, BsonAutoId.Int32);
e.Insert("col1", new BsonDocument[] { new BsonDocument {
["_id"] = 5, ["n"] = new byte[2000]
} }, BsonAutoId.Int32);
e.Insert("col1", new BsonDocument[] { new BsonDocument {
["_id"] = 6, ["n"] = new byte[2000]
} }, BsonAutoId.Int32);
// get pages
var colPage = s.CollectionPage;
var indexPage = s.LocalPages.FirstOrDefault(x => x.PageType == PageType.Index);
var dataPage1 = s.LocalPages.FirstOrDefault(x => x.PageType == PageType.Data);
var dataPage2 = s.LocalPages.FirstOrDefault(x => x.PageType == PageType.Data && x.PageID != dataPage1.PageID);
// test dataPage free space
dataPage1.FreeBytes.Should().Be(2064);
dataPage2.FreeBytes.Should().Be(2064);
colPage.FreeDataPageList.Should().Equal(uint.MaxValue, uint.MaxValue, uint.MaxValue, uint.MaxValue, dataPage2.PageID);
// delete some data
e.Delete("col1", new BsonValue[] { 2 });
// test again dataPage
dataPage1.FreeBytes.Should().Be(4092);
colPage.FreeDataPageList.Should().Equal(uint.MaxValue, uint.MaxValue, uint.MaxValue, dataPage1.PageID, dataPage2.PageID);
// clear first page
e.Delete("col1", new BsonValue[] { 1, 3 });
// page1 must be now a clean page
var emptyPage = s.LocalPages.FirstOrDefault(x => x.PageID == dataPage1.PageID);
emptyPage.PageType.Should().Be(PageType.Empty);
emptyPage.ItemsCount.Should().Be(0);
emptyPage.FreeBytes.Should().Be(8160);
t.Pages.DeletedPages.Should().Be(1);
t.Pages.FirstDeletedPageID.Should().Be(emptyPage.PageID);
t.Pages.LastDeletedPageID.Should().Be(emptyPage.PageID);
}
}