| public ResolveReference ( ObjectName refName ) : ObjectName | ||
| refName | ObjectName | |
| return | ObjectName | |
private ObjectName ResolveGroupMax(SqlQueryExpression queryExpression, QueryExpressionFrom queryFrom)
{
var groupMax = queryExpression.GroupMax;
if (groupMax != null)
{
var variable = queryFrom.ResolveReference(groupMax);
if (variable == null)
{
throw new InvalidOperationException(String.Format("The GROUP MAX column '{0}' was not found.", groupMax));
}
groupMax = variable;
}
return(groupMax);
}
private static IQueryPlanNode PlanForOrderBy(IQueryPlanNode plan, IList<SortColumn> orderBy, QueryExpressionFrom queryFrom, IList<SelectColumn> selectedColumns)
{
// Sort on the ORDER BY clause
if (orderBy.Count > 0) {
int sz = orderBy.Count;
var orderList = new ObjectName[sz];
var ascendingList = new bool[sz];
var functionOrders = new List<SqlExpression>();
for (int i = 0; i < sz; ++i) {
var column = orderBy[i];
SqlExpression exp = column.Expression;
ascendingList[i] = column.Ascending;
var v = exp.AsReferenceName();
if (v != null) {
var newV = queryFrom.ResolveReference(v);
if (newV == null)
throw new InvalidOperationException(String.Format("Could not resolve ORDER BY column '{0}' in expression", v));
newV = ReplaceAliasedVariable(newV, selectedColumns);
orderList[i] = newV;
} else {
// Otherwise we must be ordering by an expression such as
// '0 - a'.
// Resolve the expression,
exp = exp.Prepare(queryFrom.ExpressionPreparer);
// Make sure we substitute any aliased columns in the order by
// columns.
exp = ReplaceAliasedVariables(exp, selectedColumns);
// The new ordering functions are called 'FUNCTIONTABLE.#ORDER-n'
// where n is the number of the ordering expression.
orderList[i] = new ObjectName(FunctionTableName, "#ORDER-" + functionOrders.Count);
functionOrders.Add(exp);
}
}
// If there are functional orderings,
// For this we must define a new FunctionTable with the expressions,
// then order by those columns, and then use another SubsetNode
// command node.
int fsz = functionOrders.Count;
if (fsz > 0) {
var funs = new SqlExpression[fsz];
var fnames = new String[fsz];
for (int n = 0; n < fsz; ++n) {
funs[n] = functionOrders[n];
fnames[n] = "#ORDER-" + n;
}
if (plan is SubsetNode) {
// If the top plan is a SubsetNode then we use the
// information from it to create a new SubsetNode that
// doesn't include the functional orders we have attached here.
var topSubsetNode = (SubsetNode)plan;
var mappedNames = topSubsetNode.AliasColumnNames;
// Defines the sort functions
plan = new CreateFunctionsNode(plan, funs, fnames);
// Then plan the sort
plan = new SortNode(plan, orderList, ascendingList);
// Then plan the subset
plan = new SubsetNode(plan, mappedNames, mappedNames);
} else {
// Defines the sort functions
plan = new CreateFunctionsNode(plan, funs, fnames);
// Plan the sort
plan = new SortNode(plan, orderList, ascendingList);
}
} else {
// No functional orders so we only need to sort by the columns
// defined.
plan = new SortNode(plan, orderList, ascendingList);
}
}
return plan;
}
private ObjectName ResolveGroupMax(SqlQueryExpression queryExpression, QueryExpressionFrom queryFrom)
{
var groupMax = queryExpression.GroupMax;
if (groupMax != null) {
var variable = queryFrom.ResolveReference(groupMax);
if (variable == null)
throw new InvalidOperationException(String.Format("The GROUP MAX column '{0}' was not found.", groupMax));
groupMax = variable;
}
return groupMax;
}
private static IQueryPlanNode PlanForOrderBy(IQueryPlanNode plan, IList <SortColumn> orderBy, QueryExpressionFrom queryFrom, IList <SelectColumn> selectedColumns)
{
// Sort on the ORDER BY clause
if (orderBy.Count > 0)
{
int sz = orderBy.Count;
var orderList = new ObjectName[sz];
var ascendingList = new bool[sz];
var functionOrders = new List <SqlExpression>();
for (int i = 0; i < sz; ++i)
{
var column = orderBy[i];
SqlExpression exp = column.Expression;
ascendingList[i] = column.Ascending;
var v = exp.AsReferenceName();
if (v != null)
{
var newV = queryFrom.ResolveReference(v);
if (newV == null)
{
throw new InvalidOperationException(String.Format("Could not resolve ORDER BY column '{0}' in expression", v));
}
newV = ReplaceAliasedVariable(newV, selectedColumns);
orderList[i] = newV;
}
else
{
// Otherwise we must be ordering by an expression such as
// '0 - a'.
// Resolve the expression,
exp = exp.Prepare(queryFrom.ExpressionPreparer);
// Make sure we substitute any aliased columns in the order by
// columns.
exp = ReplaceAliasedVariables(exp, selectedColumns);
// The new ordering functions are called 'FUNCTIONTABLE.#ORDER-n'
// where n is the number of the ordering expression.
orderList[i] = new ObjectName(FunctionTableName, "#ORDER-" + functionOrders.Count);
functionOrders.Add(exp);
}
}
// If there are functional orderings,
// For this we must define a new FunctionTable with the expressions,
// then order by those columns, and then use another SubsetNode
// command node.
int fsz = functionOrders.Count;
if (fsz > 0)
{
var funs = new SqlExpression[fsz];
var fnames = new String[fsz];
for (int n = 0; n < fsz; ++n)
{
funs[n] = functionOrders[n];
fnames[n] = "#ORDER-" + n;
}
if (plan is SubsetNode)
{
// If the top plan is a SubsetNode then we use the
// information from it to create a new SubsetNode that
// doesn't include the functional orders we have attached here.
var topSubsetNode = (SubsetNode)plan;
var mappedNames = topSubsetNode.AliasColumnNames;
// Defines the sort functions
plan = new CreateFunctionsNode(plan, funs, fnames);
// Then plan the sort
plan = new SortNode(plan, orderList, ascendingList);
// Then plan the subset
plan = new SubsetNode(plan, mappedNames, mappedNames);
}
else
{
// Defines the sort functions
plan = new CreateFunctionsNode(plan, funs, fnames);
// Plan the sort
plan = new SortNode(plan, orderList, ascendingList);
}
}
else
{
// No functional orders so we only need to sort by the columns
// defined.
plan = new SortNode(plan, orderList, ascendingList);
}
}
return(plan);
}
public static QueryExpressionFrom Create(IRequest context, SqlQueryExpression expression)
{
// Get the 'from_clause' from the table expression
var fromClause = expression.FromClause;
var ignoreCase = context.Query.IgnoreIdentifiersCase();
var queryFrom = new QueryExpressionFrom(ignoreCase);
foreach (var fromTable in fromClause.AllTables) {
var uniqueKey = fromTable.UniqueKey;
var alias = fromTable.Alias;
if (fromTable.IsSubQuery) {
// eg. FROM ( SELECT id FROM Part )
var subQuery = fromTable.SubQuery;
var subQueryFrom = Create(context, subQuery);
// The aliased name of the table
ObjectName aliasTableName = null;
if (alias != null)
aliasTableName = new ObjectName(alias);
// Add to list of sub-query tables to add to command,
queryFrom.AddTable(new FromTableSubQuerySource(ignoreCase, uniqueKey, subQuery, subQueryFrom, aliasTableName));
} else {
// Else must be a standard command table,
string name = fromTable.Name;
// Resolve to full table name
var tableName = context.Query.ResolveTableName(name);
if (!context.Query.TableExists(tableName))
throw new InvalidOperationException(String.Format("Table '{0}' was not found.", tableName));
ObjectName givenName = null;
if (alias != null)
givenName = new ObjectName(alias);
// Get the ITableQueryInfo object for this table name (aliased).
ITableQueryInfo tableQueryInfo = context.Query.GetTableQueryInfo(tableName, givenName);
queryFrom.AddTable(new FromTableDirectSource(ignoreCase, tableQueryInfo, uniqueKey, givenName, tableName));
}
}
// Set up functions, aliases and exposed variables for this from set,
foreach (var selectColumn in expression.SelectColumns) {
// Is this a glob? (eg. Part.* )
if (selectColumn.IsGlob) {
// Find the columns globbed and add to the 'selectedColumns' result.
if (selectColumn.IsAll) {
queryFrom.ExposeAllColumns();
} else {
// Otherwise the glob must be of the form '[table name].*'
queryFrom.ExposeColumns(selectColumn.TableName);
}
} else {
// Otherwise must be a standard column reference. Note that at this
// time we aren't sure if a column expression is correlated and is
// referencing an outer source. This means we can't verify if the
// column expression is valid or not at this point.
// If this column is aliased, add it as a function reference to the
// select expression
string alias = selectColumn.Alias;
var v = selectColumn.Expression.AsReferenceName();
bool aliasMatchV = (v != null && alias != null &&
queryFrom.CompareStrings(v.Name, alias));
if (alias != null && !aliasMatchV) {
queryFrom.AddExpression(new ExpressionReference(selectColumn.Expression, alias));
queryFrom.ExposeColumn(new ObjectName(alias));
} else if (v != null) {
var resolved = queryFrom.ResolveReference(v);
queryFrom.ExposeColumn(resolved ?? v);
} else {
string funName = selectColumn.Expression.ToString();
queryFrom.AddExpression(new ExpressionReference(selectColumn.Expression, funName));
queryFrom.ExposeColumn(new ObjectName(funName));
}
}
}
return queryFrom;
}
public static QueryExpressionFrom Create(IRequest context, SqlQueryExpression expression)
{
// Get the 'from_clause' from the table expression
var fromClause = expression.FromClause;
var ignoreCase = context.Query.IgnoreIdentifiersCase();
var queryFrom = new QueryExpressionFrom(ignoreCase);
foreach (var fromTable in fromClause.AllTables)
{
var uniqueKey = fromTable.UniqueKey;
var alias = fromTable.Alias;
if (fromTable.IsSubQuery)
{
// eg. FROM ( SELECT id FROM Part )
var subQuery = fromTable.SubQuery;
var subQueryFrom = Create(context, subQuery);
// The aliased name of the table
ObjectName aliasTableName = null;
if (alias != null)
{
aliasTableName = new ObjectName(alias);
}
// Add to list of sub-query tables to add to command,
queryFrom.AddTable(new FromTableSubQuerySource(ignoreCase, uniqueKey, subQuery, subQueryFrom, aliasTableName));
}
else
{
// Else must be a standard command table,
string name = fromTable.Name;
// Resolve to full table name
var tableName = context.Query.ResolveTableName(name);
if (!context.Query.TableExists(tableName))
{
throw new InvalidOperationException(String.Format("Table '{0}' was not found.", tableName));
}
ObjectName givenName = null;
if (alias != null)
{
givenName = new ObjectName(alias);
}
// Get the ITableQueryInfo object for this table name (aliased).
ITableQueryInfo tableQueryInfo = context.Query.GetTableQueryInfo(tableName, givenName);
queryFrom.AddTable(new FromTableDirectSource(ignoreCase, tableQueryInfo, uniqueKey, givenName, tableName));
}
}
// Set up functions, aliases and exposed variables for this from set,
foreach (var selectColumn in expression.SelectColumns)
{
// Is this a glob? (eg. Part.* )
if (selectColumn.IsGlob)
{
// Find the columns globbed and add to the 'selectedColumns' result.
if (selectColumn.IsAll)
{
queryFrom.ExposeAllColumns();
}
else
{
// Otherwise the glob must be of the form '[table name].*'
queryFrom.ExposeColumns(selectColumn.TableName);
}
}
else
{
// Otherwise must be a standard column reference. Note that at this
// time we aren't sure if a column expression is correlated and is
// referencing an outer source. This means we can't verify if the
// column expression is valid or not at this point.
// If this column is aliased, add it as a function reference to the
// select expression
string alias = selectColumn.Alias;
var v = selectColumn.Expression.AsReferenceName();
bool aliasMatchV = (v != null && alias != null &&
queryFrom.CompareStrings(v.Name, alias));
if (alias != null && !aliasMatchV)
{
queryFrom.AddExpression(new ExpressionReference(selectColumn.Expression, alias));
queryFrom.ExposeColumn(new ObjectName(alias));
}
else if (v != null)
{
var resolved = queryFrom.ResolveReference(v);
queryFrom.ExposeColumn(resolved ?? v);
}
else
{
string funName = selectColumn.Expression.ToString();
queryFrom.AddExpression(new ExpressionReference(selectColumn.Expression, funName));
queryFrom.ExposeColumn(new ObjectName(funName));
}
}
}
return(queryFrom);
}
