public IEnumerable <IColumnRelationship> ParseBooleanComparisonExpression(BooleanComparisonExpression booleanComparisonExpression, IDictionary <string, ITable> tableByAliasIdentifier, IList <int> booleanComparisonExpressionIdentifiers, RelationshipOrigin relationshipOrigin)
{
if (booleanComparisonExpression.ComparisonType == BooleanComparisonType.NotEqualToBrackets || booleanComparisonExpression.ComparisonType == BooleanComparisonType.NotEqualToExclamation)
{
yield break;
}
var columnReferenceExpressions = _visitorProvider.GetColumnReferenceExpressions(booleanComparisonExpression).AsList();
if (columnReferenceExpressions.Count != 2)
{
yield break;
}
var fromColumnReferenceExpression = columnReferenceExpressions[0];
if (!TryParseColumn(fromColumnReferenceExpression, tableByAliasIdentifier, out IColumn fromColumn))
{
yield break;
}
var toColumnReferenceExpression = columnReferenceExpressions[1];
if (!TryParseColumn(toColumnReferenceExpression, tableByAliasIdentifier, out IColumn toColumn))
{
yield break;
}
var booleanComparisonExpressionIdentifier = booleanComparisonExpression.FirstTokenIndex + booleanComparisonExpression.LastTokenIndex;
if (booleanComparisonExpressionIdentifiers.Contains(booleanComparisonExpressionIdentifier))
{
yield break;
}
booleanComparisonExpressionIdentifiers.Add(booleanComparisonExpressionIdentifier);
var columnRelationship = new ColumnRelationship(fromColumn, toColumn, relationshipOrigin);
yield return(columnRelationship);
}
public IEnumerable <IColumnRelationship> ParseViewTableColumnToBaseTableColumnRelationships(TSqlStatement tsqlStatement, string contextualServerName, string contextualDatabaseName, RelationshipOrigin relationshipOrigin)
{
var viewStatementBody = tsqlStatement as ViewStatementBody;
if (viewStatementBody == null)
{
yield break;
}
if (!TryParseTable(contextualServerName, contextualDatabaseName, viewStatementBody.SchemaObjectName, out ITable viewTable))
{
yield break;
}
var selectStatement = viewStatementBody.SelectStatement;
var queryExpression = selectStatement.QueryExpression;
var querySpecification = queryExpression as QuerySpecification;
if (!(queryExpression is QuerySpecification))
{
yield break;
}
var selectElements = querySpecification.SelectElements;
if (viewTable.Columns.Count != selectElements.Count)
{
yield break;
}
var viewStatementFromClause = querySpecification.FromClause;
if (!TryParseTableByAliasIdentifier(viewStatementFromClause, contextualServerName, contextualDatabaseName, out IDictionary <string, ITable> viewTableByAliasIdentifier))
{
yield break;
}
for (var index = 0; index < selectElements.Count; index++)
{
var selectElement = selectElements[index];
var selectScalarExpression = (SelectScalarExpression)selectElement;
var scalarExpression = selectScalarExpression.Expression;
var columnReferenceExpression = scalarExpression as ColumnReferenceExpression;
if (!(scalarExpression is ColumnReferenceExpression))
{
continue;
}
var viewColumns = viewTable.Columns.AsList();
var viewTableColumn = viewColumns[index];
if (!TryParseColumn(columnReferenceExpression, viewTableByAliasIdentifier, out IColumn baseTableColumn))
{
continue;
}
var columnRelationship = new ColumnRelationship(viewTableColumn, baseTableColumn, relationshipOrigin);
yield return(columnRelationship);
}
}