public void Populate()
{
if (DefinitionType == TableDefinitionType.FREE)
{
return; // Nothing to do
}
Length = 0;
if (DefinitionType == TableDefinitionType.PROJECTION) // There are import dimensions so copy data from another set (projection of another set)
{
List<DcColumn> inColumns = InputColumns.Where(d => d.GetData().IsAppendData).ToList();
foreach(DcColumn inColumn in inColumns)
{
inColumn.GetData().Translate();
inColumn.GetData().Evaluate(); // Delegate to column evaluation - it will add records from column expression
}
}
else if (DefinitionType == TableDefinitionType.PRODUCT) // Product of local sets (no project/de-project from another set)
{
// Input variable for where formula
DcVariable thisVariable = new Variable(this.Schema.Name, this.Name, "this");
thisVariable.TypeSchema = this.Schema;
thisVariable.TypeTable = this;
// Evaluator expression for where formula
ExprNode outputExpr = this.WhereExpr;
if(outputExpr != null)
{
outputExpr.OutputVariable.SchemaName = this.Schema.Name;
outputExpr.OutputVariable.TypeName = "Boolean";
outputExpr.OutputVariable.TypeSchema = this.Schema;
outputExpr.OutputVariable.TypeTable = this.Schema.GetPrimitiveType("Boolean");
outputExpr.Resolve(this.Space, new List<DcVariable>() { thisVariable });
outputExpr.EvaluateBegin();
}
DcTableWriter tableWriter = this.GetTableWriter();
tableWriter.Open();
//
// Find all local greater dimensions to be varied (including the super-dim)
//
DcColumn[] cols = Columns.Where(x => x.IsKey && !x.IsPrimitive).ToArray();
int colCount = cols.Length; // Dimensionality - how many free dimensions
object[] vals = new object[colCount]; // A record with values for each free dimension being varied
// Prepare columns
foreach (DcColumn col in cols)
{
col.GetData().AutoIndex = true; // We need true to correctly evaluate where condition and correctly remove last element if it is wrong
//col.GetData().Nullify();
}
//
// The current state of the search procedure
//
Rowid[] lengths = new Rowid[colCount]; // Size of each dimension being varied (how many offsets in each dimension)
for (int i = 0; i < colCount; i++) lengths[i] = cols[i].Output.GetData().Length;
Rowid[] offsets = new Rowid[colCount]; // The current point/offset for each dimensions during search
for (int i = 0; i < colCount; i++) offsets[i] = -1;
int top = -1; // The current level/top where we change the offset. Depth of recursion.
do ++top; while (top < colCount && lengths[top] == 0);
// Alternative recursive iteration: http://stackoverflow.com/questions/13655299/c-sharp-most-efficient-way-to-iterate-through-multiple-arrays-list
while (top >= 0)
{
if (top == colCount) // New element is ready. Process it.
{
// Initialize a record and append it
for (int i = 0; i < colCount; i++)
{
vals[i] = offsets[i];
}
Rowid input = tableWriter.Append(cols, vals);
//
// Now check if this appended element satisfies the where expression and if not then remove it
//
if (outputExpr != null)
{
// Set 'this' variable to the last elements (that has been just appended) which will be read by the expression
thisVariable.SetValue(this.GetData().Length - 1);
// Evaluate expression
outputExpr.Evaluate();
bool satisfies = (bool)outputExpr.OutputVariable.GetValue();
if (!satisfies)
{
Length = Length - 1; // Remove elements
}
}
top--;
while (top >= 0 && lengths[top] == 0) // Go up by skipping empty dimensions and reseting
{ offsets[top--] = -1; }
}
else
{
// Find the next valid offset
offsets[top]++;
if (offsets[top] < lengths[top]) // Offset chosen
{
do ++top;
while (top < colCount && lengths[top] == 0); // Go up (forward) by skipping empty dimensions
}
else // Level is finished. Go back.
{
do { offsets[top--] = -1; }
while (top >= 0 && lengths[top] == 0); // Go down (backward) by skipping empty dimensions and reseting
}
}
}
// Prepare columns
foreach (DcColumn col in cols)
{
col.GetData().Reindex();
col.GetData().AutoIndex = true;
}
if (tableWriter != null)
{
tableWriter.Close();
}
if (outputExpr != null)
{
outputExpr.EvaluateEnd();
}
}
else
{
throw new NotImplementedException("This table definition type is not implemented and cannot be populated.");
}
}
public static void CreateSampleData(DcSchema schema)
{
//
// Fill sample data in "Table 1"
//
DcTable t1 = schema.GetSubTable("Table 1");
DcColumn c11 = t1.GetColumn("Column 11");
DcColumn c12 = t1.GetColumn("Column 12");
DcColumn c13 = t1.GetColumn("Column 13");
DcColumn c14 = t1.GetColumn("Column 14");
DcColumn[] cols = new DcColumn[] { c11, c12, c13, c14 };
object[] vals = new object[4];
DcTableWriter w1 = t1.GetData().GetTableWriter();
vals[0] = 20;
vals[1] = "Record 0";
vals[2] = 20.0;
vals[3] = 20.0;
w1.Append(cols, vals);
vals[0] = 10;
vals[1] = "Record 1";
vals[2] = 10.0;
vals[3] = 20.0;
w1.Append(cols, vals);
vals[0] = 30;
vals[1] = "Record 2";
vals[2] = 30.0;
vals[3] = 20.0;
w1.Append(cols, vals);
//
// Fill sample data in "Table 2"
//
DcTable t2 = schema.GetSubTable("Table 2");
DcColumn c21 = t2.GetColumn("Column 21");
DcColumn c22 = t2.GetColumn("Column 22");
DcColumn c23 = t2.GetColumn("Column 23");
DcColumn c24 = t2.GetColumn("Table 1");
cols = new DcColumn[] { c21, c22, c23, c24 };
vals = new object[4];
DcTableWriter w2 = t2.GetData().GetTableWriter();
vals[0] = "Value A";
vals[1] = 20;
vals[2] = 40.0;
vals[3] = 0;
w2.Append(cols, vals);
vals[0] = "Value A";
vals[1] = 30;
vals[2] = 40.0;
vals[3] = 1;
w2.Append(cols, vals);
vals[0] = "Value A";
vals[1] = 30;
vals[2] = 50.0;
vals[3] = 1;
w2.Append(cols, vals);
vals[0] = "Value B";
vals[1] = 30;
vals[2] = 50.0;
vals[3] = 1;
w2.Append(cols, vals);
}