func (s *selectNode) addRender(target parser.SelectExpr) *roachpb.Error {
// outputName will be empty if the target is not aliased.
outputName := string(target.As)
if isStar, cols, exprs, err := checkRenderStar(target, &s.table, s.qvals); err != nil {
s.pErr = roachpb.NewError(err)
return s.pErr
} else if isStar {
s.columns = append(s.columns, cols...)
s.render = append(s.render, exprs...)
return nil
}
// When generating an output column name it should exactly match the original
// expression, so determine the output column name before we perform any
// manipulations to the expression.
outputName = getRenderColName(target)
// Resolve qualified names. This has the side-effect of normalizing any
// qualified name found.
var resolved parser.Expr
var err error
if resolved, err = s.resolveQNames(target.Expr); err != nil {
s.pErr = roachpb.NewError(err)
return s.pErr
}
if resolved, s.pErr = s.planner.expandSubqueries(resolved, 1); s.pErr != nil {
return s.pErr
}
var typ parser.Datum
typ, err = resolved.TypeCheck(s.planner.evalCtx.Args)
s.pErr = roachpb.NewError(err)
if s.pErr != nil {
return s.pErr
}
var normalized parser.Expr
normalized, err = s.planner.parser.NormalizeExpr(s.planner.evalCtx, resolved)
s.pErr = roachpb.NewError(err)
if s.pErr != nil {
return s.pErr
}
s.render = append(s.render, normalized)
if target.As == "" {
switch t := target.Expr.(type) {
case *parser.QualifiedName:
// If the expression is a qualified name, use the column name, not the
// full qualification as the column name to return.
outputName = t.Column()
}
}
s.columns = append(s.columns, ResultColumn{Name: outputName, Typ: typ})
return nil
}
func sameTypeExprs(left, right parser.Expr) (bool, error) {
dummyLeft, err := left.TypeCheck(nil)
if err != nil || dummyLeft == parser.DNull {
return false, err
}
dummyRight, err := right.TypeCheck(nil)
if err != nil || dummyRight == parser.DNull {
return false, err
}
return !dummyLeft.TypeEqual(dummyRight), nil
}
func (n *scanNode) addRender(target parser.SelectExpr) *roachpb.Error {
// When generating an output column name it should exactly match the original
// expression, so determine the output column name before we perform any
// manipulations to the expression (such as star expansion).
var outputName string
if target.As != "" {
outputName = string(target.As)
} else {
outputName = target.Expr.String()
}
// If a QualifiedName has a StarIndirection suffix we need to match the
// prefix of the qualified name to one of the tables in the query and
// then expand the "*" into a list of columns.
if qname, ok := target.Expr.(*parser.QualifiedName); ok {
if n.pErr = roachpb.NewError(qname.NormalizeColumnName()); n.pErr != nil {
return n.pErr
}
if qname.IsStar() {
if n.desc == nil {
return roachpb.NewUErrorf("\"%s\" with no tables specified is not valid", qname)
}
if target.As != "" {
return roachpb.NewUErrorf("\"%s\" cannot be aliased", qname)
}
tableName := qname.Table()
if tableName != "" && !equalName(n.desc.Alias, tableName) {
return roachpb.NewUErrorf("table \"%s\" not found", tableName)
}
if n.isSecondaryIndex {
for _, id := range n.index.ColumnIDs {
var col *ColumnDescriptor
if col, n.pErr = n.desc.FindColumnByID(id); n.pErr != nil {
return n.pErr
}
qval := n.getQVal(*col)
n.columns = append(n.columns, resultColumn{name: col.Name, typ: qval.datum})
n.render = append(n.render, qval)
}
} else {
for _, col := range n.desc.VisibleColumns() {
qval := n.getQVal(col)
n.columns = append(n.columns, resultColumn{name: col.Name, typ: qval.datum})
n.render = append(n.render, qval)
}
}
return nil
}
}
// Resolve qualified names. This has the side-effect of normalizing any
// qualified name found.
var resolved parser.Expr
if resolved, n.pErr = n.resolveQNames(target.Expr); n.pErr != nil {
return n.pErr
}
if resolved, n.pErr = n.planner.expandSubqueries(resolved, 1); n.pErr != nil {
return n.pErr
}
var typ parser.Datum
var err error
typ, err = resolved.TypeCheck(n.planner.evalCtx.Args)
n.pErr = roachpb.NewError(err)
if n.pErr != nil {
return n.pErr
}
var normalized parser.Expr
normalized, err = n.planner.parser.NormalizeExpr(n.planner.evalCtx, resolved)
n.pErr = roachpb.NewError(err)
if n.pErr != nil {
return n.pErr
}
n.render = append(n.render, normalized)
if target.As == "" {
switch t := target.Expr.(type) {
case *parser.QualifiedName:
// If the expression is a qualified name, use the column name, not the
// full qualification as the column name to return.
outputName = t.Column()
}
}
n.columns = append(n.columns, resultColumn{name: outputName, typ: typ})
return nil
}