/// <summary>
/// Dispose of this Table instance.
/// </summary>
public virtual void Dispose()
{
if (!_initialize)
{
_keyspace.RemoveTable(this);
_keyspace = null;
Columns.Dispose();
}
}
/// <summary>
/// Add a Keyspace to this DataCluster.
/// </summary>
internal void AddKeyspace(Keyspace keyspace)
{
_lock.Take();
// if the default keyspace hasn't been set
if (_defaultKeyspace == null)
{
_defaultKeyspace = keyspace;
}
Keyspaces.Add(keyspace.Metadata.Name, keyspace);
_lock.Release();
}
/// <summary>
/// Initialize a new query for the specified table and keyspace.
/// </summary>
public Query(Table table, Keyspace keyspace, int pageSize = -1)
{
Table = table;
Keyspace = keyspace;
_pageSize = pageSize == -1 ? Table.DefaultPageSize : pageSize;
// initialize the collections of value sets
Keywords = new ArrayRig <Cql>(3);
Sets = new ArrayRig <int>(3);
Values = new ArrayRig <object>(Table.Columns.Count);
Columns = new ArrayRig <Column>(Table.Columns.Count);
}
/// <summary>
/// Remove a Keyspace from this DataCluster.
/// </summary>
internal void RemoveKeyspace(Keyspace keyspace)
{
_lock.Take();
// if the keyspace removed is the default keyspace
Keyspaces.Remove(keyspace.Metadata.Name);
if (_defaultKeyspace == keyspace)
{
if (Keyspaces.Count == 0)
{
_defaultKeyspace = null;
}
else
{
foreach (var entry in Keyspaces)
{
_defaultKeyspace = entry.Value;
break;
}
}
}
_lock.Release();
}
//-------------------------------------------//
/// <summary>
/// Initialize this Table instance.
/// </summary>
private void Initialize()
{
// take the initialize lock
_lock.Take();
// was the table initialized by another thread? yes, skip
if (!_initialize)
{
_lock.Release();
return;
}
// if the keyspace name wasn't set - get the current default
_keyspace = _keyspaceName == null ?
ManagerCql.DefaultCluster.DefaultKeyspace :
ManagerCql.DefaultCluster.GetKeyspace(_keyspaceName);
// get the table metadata
if (_keyspace.Metadata == null)
{
// create an inline timer to wait for keyspace initialization
TimeInline timer = new TimeInline(4000, () => _keyspace.Metadata != null);
// wait until timeout or keyspace metadata being populated
while (timer.Wait)
{
}
// was the metadata retrieved?
if (!timer.Success)
{
// no, error log
Log.Error("Table '" + Name + "' isn't available. Keyspace '" + _keyspaceName + "' couldn't initialize.");
_lock.Release();
return;
}
}
// get the metadata for the table - does the table exist?
if (!_keyspace.TableMetadata.TakeItem().TryGetValue(Name, out Metadata))
{
// no, create the table
_keyspace.TableMetadata.Release();
bool primaryKey = false;
// add this Table to the Keyspace
Query builder = new Query(this, _keyspace);
CqlCreateTable createQuery = new CqlCreateTable(builder);
// iterate the columns to create
foreach (Column column in Columns)
{
createQuery.With(column);
primaryKey |= column.Class == Column.ColumnClass.Primary;
}
// if there were no primary keys
if (!primaryKey)
{
Log.Error("Cannot create a Table with no primary keys.");
_lock.Release();
return;
}
// run the query and get the metadata
Metadata = createQuery;
// add the metadata to the keyspace
_keyspace.TableMetadata.TakeItem().Add(Name, Metadata);
}
_keyspace.TableMetadata.Release();
// add this table to the keyspace
_keyspace.AddTable(this);
ArrayRig <Column> newColumns = new ArrayRig <Column>(Columns);
ArrayRig <TableColumn> oldColumns = new ArrayRig <TableColumn>();
// iterate table column in the metadata
foreach (TableColumn col in Metadata.TableColumns)
{
// flag to indicate the column reference exists
bool found = false;
// iterate the columns
for (int i = Columns.Count - 1; i >= 0; --i)
{
// if the name matches
if (col.Name == Columns[i].Name)
{
// set the index
Columns[i].Index = col.Index;
// remove from add collection
newColumns.RemoveQuick(Columns[i]);
found = true;
break;
}
}
// was the column found in the metadata? no, add to be removed
if (!found)
{
oldColumns.Add(col);
}
}
// add each new column
foreach (var newColumn in newColumns)
{
// log the removal
Log.CriticalChange("A COLUMN IS ABOUT TO BE Added : " + Keyspace.Metadata.Name + Chars.Stop, 2);
// get the builder
var builder = StringBuilderCache.Get();
// append a query that will add the new column
builder.Append("ALTER TABLE ");
builder.Append(Keyspace.Metadata.Name);
builder.Append(Chars.Stop);
builder.Append(Name);
builder.Append(" ADD ");
builder.Append(newColumn.Name);
builder.Append(Chars.Space);
builder.Append(newColumn.DataType);
builder.Append(Chars.SemiColon);
// get a simple statement
var addStatement = new SimpleStatement(builder.ToString());
// execute the statement
Keyspace.Session.Execute(addStatement);
}
// iterate the old columns
foreach (var oldColumn in oldColumns)
{
// log the removal
Log.CriticalChange("A COLUMN IS ABOUT TO BE DROPPED : " + Keyspace.Metadata.Name + Chars.Stop, 10);
// get the builder
var builder = StringBuilderCache.Get();
// append a query that will remove the old column
builder.Append("ALTER TABLE ");
builder.Append(Keyspace.Metadata.Name);
builder.Append(Chars.Stop);
builder.Append(Name);
builder.Append(" DROP ");
builder.Append(oldColumn.Name);
builder.Append(Chars.SemiColon);
// get a simple statement
var removeStatement = new SimpleStatement(builder.ToString());
// execute the statement
Keyspace.Session.Execute(removeStatement);
}
// the table has been initialized
_initialize = false;
// release the lock
_lock.Release();
}
