long ReadTableId( Schema schema, string name, out bool isView, out string definition )
{
var r = new RowCursor( SysTable );
var start = new StringStart( name );
foreach( IndexFileRecord ixr in SysTableByName.From( start.Compare, false ) )
{
if ( (string)(ixr.Col[0]._O) == name )
{
long id = ixr.Col[1].L;
r.Get( id );
if ( r.V[1].L == schema.Id )
{
isView = r.V[3].L != 0;
definition = (string)r.V[4]._O;
return id;
}
}
}
isView = false; definition = null;
return -1;
}
// Functions related to Indexing.
public void InitIndex(long indexId) // Called during CREATE INDEX to index existing rows.
{
IndexFile ixf = IxDict[indexId];
var rc = new RowCursor(this);
int n = ixf.Inf.BaseIx.Length;
IndexFileRecord ixr = new IndexFileRecord(n + 1);
for (long id = 1; id <= RowCount; id += 1)
{
if (rc.Get(id))
{
// Create the IndexFileRecord to be inserted.
for (int i = 0; i < n; i += 1)
{
ixr.Col[i] = rc.V[ixf.Inf.BaseIx[i]];
}
ixr.Col[n].L = id; // Append the id of the row.
ixf.Insert(ref ixr);
}
}
Dirty = true;
}
// Indexes.
public void CreateIndex( string schemaName, string tableName, string indexName, string [] names, Exec e )
{
Table t = (Table)GetTable( schemaName, tableName, e );
long tid = t.TableId;
long indexId = GetIndexId( tid, indexName );
if ( indexId != 0 ) e.Error( "Index already exists" );
int [] colIx = new int[ names.Length ];
for ( int i=0; i < names.Length; i +=1 )
{
colIx[ i ] = t.ColumnIx( names[i], e );
}
// Create the index.
{
var r = new RowCursor( SysIndex );
r.V[1].L = tid;
r.V[2].O = indexName;
indexId = r.Insert();
}
// Create the index columns.
{
var r = new RowCursor( SysIndexCol );
r.V[1].L = tid;
r.V[2].L = indexId;
for ( int i = 0; i < names.Length; i += 1 )
{
r.V[3].L = colIx[ i ];
r.Insert();
}
}
if ( Normal )
{
t.OpenIndexes();
t.InitIndex( indexId );
}
}
public IndexInfo [] ReadIndexes( long tableId )
{
var ix = new G.List<IndexInfo>();
var r = new RowCursor( SysIndexCol );
long CurIx = 0;
int IxNum = 0;
// Use SysIndexColIndex to avoid scanning the entire SysIndexCol table.
var start = new LongStart( tableId );
foreach( IndexFileRecord ixr in SysIndexColIndex.From( start.Compare, false ) )
{
if ( ixr.Col[0].L == tableId )
{
r.Get( ixr.Col[1].L );
var ii = new IndexInfo();
ii.IndexId = r.V[2].L;
if ( ii.IndexId != CurIx ) { IxNum = 0; CurIx = ii.IndexId; }
ii.IxNum = IxNum++;
ii.ColIx = (int)r.V[3].L;
ix.Add( ii );
} else break;
}
return ix.ToArray();
}
public void CreateTable( string schemaName, string tableName, ColInfo cols, string definition, bool isView, bool alter, Exec e )
{
Schema schema = GetSchema( schemaName, true, e );
bool isView1; string definition1;
long tableId = tableId = ReadTableId( schema, tableName, out isView1, out definition1 );
if ( alter )
{
if ( tableId == 0 || !isView1 ) e.Error( "View does not exist" );
}
else if ( Normal && schema.GetCachedTable( tableName ) != null || tableId >= 0 )
e.Error( "Table/View " + schemaName + "." + tableName + " already exists" );
var r = new RowCursor( SysTable );
r.V[1].L = schema.Id;
r.V[2].O = tableName;
r.V[3].L = isView ? 1 : 0;
r.V[4].O = isView ? definition.Trim() : "";
if ( alter ) r.Update( tableId ); else tableId = r.Insert();
if ( isView ) ResetCache(); else SaveColumns( tableId, cols );
}
