Example #1
0
// Find returns the route for the symbol referenced by col.
// If a reference is found, the column's Metadata is set to point
// it. Subsequent searches will reuse this meatadata.
// If autoResolve is true, and there is only one table in the symbol table,
// then an unqualified reference is assumed to be implicitly against
// that table. The table info doesn't contain the full list of columns.
// So, any column reference is presumed valid. If a Colsyms scope is
// present, then the table scope is not searched. If a symbol is found
// in the current symtab, then isLocal is set to true. Otherwise, the
// search is continued in the outer symtab. If so, isLocal will be set
// to false. If the symbol was not found, an error is returned.
// isLocal must be checked before you can push-down (or pull-out)
// a construct.
// If a symbol was found in an outer scope, then the column reference
// is added to the Externs field.
func (st *symtab) Find(col *sqlparser.ColName, autoResolve bool) (rb *route, isLocal bool, err error) {
	if m, ok := col.Metadata.(sym); ok {
		return m.Route(), m.Symtab() == st, nil
	}
	if len(st.Colsyms) != 0 {
		name := sqlparser.SQLName(sqlparser.String(col))
		starname := sqlparser.SQLName(sqlparser.String(&sqlparser.ColName{
			Name:      "*",
			Qualifier: col.Qualifier,
		}))
		for _, colsym := range st.Colsyms {
			if name == colsym.Alias || starname == colsym.Alias || colsym.Alias == "*" {
				col.Metadata = colsym
				return colsym.Route(), true, nil
			}
		}
		if st.Outer != nil {
			// autoResolve only allowed for innermost scope.
			rb, _, err = st.Outer.Find(col, false)
			if err == nil {
				st.Externs = append(st.Externs, col)
			}
			return rb, false, err
		}
		return nil, false, fmt.Errorf("symbol %s not found", sqlparser.String(col))
	}
	qualifier := sqlparser.SQLName(sqlparser.String(col.Qualifier))
	if qualifier == "" && autoResolve && len(st.tables) == 1 {
		for _, t := range st.tables {
			qualifier = t.Alias
			break
		}
	}
	alias := st.findTable(qualifier)
	if alias == nil {
		if st.Outer != nil {
			// autoResolve only allowed for innermost scope.
			rb, _, err = st.Outer.Find(col, false)
			if err == nil {
				st.Externs = append(st.Externs, col)
			}
			return rb, false, err
		}
		return nil, false, fmt.Errorf("symbol %s not found", sqlparser.String(col))
	}
	col.Metadata = alias
	return alias.Route(), true, nil
}
Example #2
0
// PushStar pushes the '*' expression into the route.
func (rb *route) PushStar(expr *sqlparser.StarExpr) *colsym {
	colsym := newColsym(rb, rb.Symtab())
	colsym.Alias = sqlparser.SQLName(sqlparser.String(expr))
	rb.Select.SelectExprs = append(rb.Select.SelectExprs, expr)
	rb.Colsyms = append(rb.Colsyms, colsym)
	return colsym
}
Example #3
0
func convertColumnNamesToValExpr(colNames []string) []sqlparser.ValExpr {
	valExprs := make([]sqlparser.ValExpr, 0, len(colNames))
	for _, colName := range colNames {
		valExprs = append(valExprs, &sqlparser.ColName{Name: sqlparser.SQLName(colName)})
	}
	return valExprs
}
Example #4
0
// processAliasedTable produces a builder subtree for the given AliasedTableExpr.
// If the expression is a subquery, then the the route built for it will contain
// the entire subquery tree in the from clause, as if it was a table.
// The symtab entry for the query will be a tabsym where the columns
// will be built from the select expressions of the subquery.
// Since the table aliases only contain vindex columns, we'll follow
// the same rule: only columns from the subquery that are identified as
// vindex columns will be added to the tabsym.
// A symtab symbol can only point to a route. This means that we canoot
// support complex joins in subqueries yet.
func processAliasedTable(tableExpr *sqlparser.AliasedTableExpr, vschema VSchema) (builder, error) {
	switch expr := tableExpr.Expr.(type) {
	case *sqlparser.TableName:
		eroute, table, err := getTablePlan(expr, vschema)
		if err != nil {
			return nil, err
		}
		alias := sqlparser.SQLName(sqlparser.String(expr))
		astName := expr.Name
		if tableExpr.As != "" {
			alias = tableExpr.As
			astName = alias
		}
		return newRoute(
			sqlparser.TableExprs([]sqlparser.TableExpr{tableExpr}),
			eroute,
			table,
			vschema,
			alias,
			astName,
		), nil
	case *sqlparser.Subquery:
		sel, ok := expr.Select.(*sqlparser.Select)
		if !ok {
			return nil, errors.New("unsupported: union operator in subqueries")
		}
		subplan, err := processSelect(sel, vschema, nil)
		if err != nil {
			return nil, err
		}
		subroute, ok := subplan.(*route)
		if !ok {
			return nil, errors.New("unsupported: complex join in subqueries")
		}
		table := &vindexes.Table{
			Keyspace: subroute.ERoute.Keyspace,
		}
		for _, colsyms := range subroute.Colsyms {
			if colsyms.Vindex == nil {
				continue
			}
			table.ColVindexes = append(table.ColVindexes, &vindexes.ColVindex{
				Col:    string(colsyms.Alias),
				Vindex: colsyms.Vindex,
			})
		}
		rtb := newRoute(
			sqlparser.TableExprs([]sqlparser.TableExpr{tableExpr}),
			subroute.ERoute,
			table,
			vschema,
			tableExpr.As,
			tableExpr.As,
		)
		subroute.Redirect = rtb
		return rtb, nil
	}
	panic("unreachable")
}
Example #5
0
func buildOrderByClause(splitColumns []string) sqlparser.OrderBy {
	result := make(sqlparser.OrderBy, 0, len(splitColumns))
	for _, splitColumn := range splitColumns {
		result = append(result,
			&sqlparser.Order{
				Expr:      &sqlparser.ColName{Name: sqlparser.SQLName(splitColumn)},
				Direction: sqlparser.AscScr,
			},
		)
	}
	return result
}
Example #6
0
func convertColumnNamesToSelectExprs(columnNames []string) sqlparser.SelectExprs {
	result := make([]sqlparser.SelectExpr, 0, len(columnNames))
	for _, columnName := range columnNames {
		result = append(result,
			&sqlparser.NonStarExpr{
				Expr: &sqlparser.ColName{
					Name: sqlparser.SQLName(columnName),
				},
			})
	}
	return result
}
Example #7
0
// getWhereClause returns a whereClause based on desired upper and lower
// bounds for primary key.
func (qs *QuerySplitter) getWhereClause(whereClause *sqlparser.Where, bindVars map[string]interface{}, start, end sqltypes.Value) *sqlparser.Where {
	var startClause *sqlparser.ComparisonExpr
	var endClause *sqlparser.ComparisonExpr
	var clauses sqlparser.BoolExpr
	// No upper or lower bound, just return the where clause of original query
	if start.IsNull() && end.IsNull() {
		return whereClause
	}
	pk := &sqlparser.ColName{
		Name: sqlparser.SQLName(qs.splitColumn),
	}
	if !start.IsNull() {
		startClause = &sqlparser.ComparisonExpr{
			Operator: sqlparser.GreaterEqualStr,
			Left:     pk,
			Right:    sqlparser.ValArg([]byte(":" + startBindVarName)),
		}
		bindVars[startBindVarName] = start.ToNative()
	}
	// splitColumn < end
	if !end.IsNull() {
		endClause = &sqlparser.ComparisonExpr{
			Operator: sqlparser.LessThanStr,
			Left:     pk,
			Right:    sqlparser.ValArg([]byte(":" + endBindVarName)),
		}
		bindVars[endBindVarName] = end.ToNative()
	}
	if startClause == nil {
		clauses = endClause
	} else {
		if endClause == nil {
			clauses = startClause
		} else {
			// splitColumn >= start AND splitColumn < end
			clauses = &sqlparser.AndExpr{
				Left:  startClause,
				Right: endClause,
			}
		}
	}
	if whereClause != nil {
		clauses = &sqlparser.AndExpr{
			Left:  &sqlparser.ParenBoolExpr{Expr: whereClause.Expr},
			Right: &sqlparser.ParenBoolExpr{Expr: clauses},
		}
	}
	return &sqlparser.Where{
		Type: sqlparser.WhereStr,
		Expr: clauses,
	}
}
Example #8
0
// getWhereClause returns a whereClause based on desired upper and lower
// bounds for primary key.
func (qs *QuerySplitter) getWhereClause(start, end sqltypes.Value) *sqlparser.Where {
	var startClause *sqlparser.ComparisonExpr
	var endClause *sqlparser.ComparisonExpr
	var clauses sqlparser.BoolExpr
	// No upper or lower bound, just return the where clause of original query
	if start.IsNull() && end.IsNull() {
		return qs.sel.Where
	}
	pk := &sqlparser.ColName{
		Name: sqlparser.SQLName(qs.splitColumn),
	}
	// splitColumn >= start
	if !start.IsNull() {
		startClause = &sqlparser.ComparisonExpr{
			Operator: sqlparser.AST_GE,
			Left:     pk,
			Right:    sqlparser.NumVal((start).Raw()),
		}
	}
	// splitColumn < end
	if !end.IsNull() {
		endClause = &sqlparser.ComparisonExpr{
			Operator: sqlparser.AST_LT,
			Left:     pk,
			Right:    sqlparser.NumVal((end).Raw()),
		}
	}
	if startClause == nil {
		clauses = endClause
	} else {
		if endClause == nil {
			clauses = startClause
		} else {
			// splitColumn >= start AND splitColumn < end
			clauses = &sqlparser.AndExpr{
				Left:  startClause,
				Right: endClause,
			}
		}
	}
	if qs.sel.Where != nil {
		clauses = &sqlparser.AndExpr{
			Left:  qs.sel.Where.Expr,
			Right: clauses,
		}
	}
	return &sqlparser.Where{
		Type: sqlparser.AST_WHERE,
		Expr: clauses,
	}
}
Example #9
0
// GenerateSelectSubquery generates the subquery for selects.
func GenerateSelectSubquery(sel *sqlparser.Select, tableInfo *schema.Table, index string) *sqlparser.ParsedQuery {
	hint := &sqlparser.IndexHints{Type: sqlparser.UseStr, Indexes: []sqlparser.SQLName{sqlparser.SQLName(index)}}
	tableExpr := sel.From[0].(*sqlparser.AliasedTableExpr)
	savedHint := tableExpr.Hints
	tableExpr.Hints = hint
	defer func() {
		tableExpr.Hints = savedHint
	}()
	return GenerateSubquery(
		tableInfo.Indexes[0].Columns,
		tableExpr,
		sel.Where,
		sel.OrderBy,
		sel.Limit,
		false,
	)
}
Example #10
0
// PushSelect pushes the select expression into the route.
func (rb *route) PushSelect(expr *sqlparser.NonStarExpr, _ *route) (colsym *colsym, colnum int, err error) {
	colsym = newColsym(rb, rb.Symtab())
	if expr.As != "" {
		colsym.Alias = expr.As
	}
	if col, ok := expr.Expr.(*sqlparser.ColName); ok {
		if colsym.Alias == "" {
			colsym.Alias = sqlparser.SQLName(sqlparser.String(col))
		}
		colsym.Vindex = rb.Symtab().Vindex(col, rb, true)
		colsym.Underlying = newColref(col)
	} else {
		if rb.IsRHS {
			return nil, 0, errors.New("unsupported: complex left join and column expressions")
		}
	}
	rb.Select.SelectExprs = append(rb.Select.SelectExprs, expr)
	rb.Colsyms = append(rb.Colsyms, colsym)
	return colsym, len(rb.Colsyms) - 1, nil
}
Example #11
0
func buildIndexPlan(ins *sqlparser.Insert, tablename string, colVindex *ColVindex, plan *Plan) error {
	pos := -1
	for i, column := range ins.Columns {
		if colVindex.Col == sqlparser.GetColName(column.(*sqlparser.NonStarExpr).Expr) {
			pos = i
			break
		}
	}
	if pos == -1 {
		pos = len(ins.Columns)
		ins.Columns = append(ins.Columns, &sqlparser.NonStarExpr{Expr: &sqlparser.ColName{Name: sqlparser.SQLName(colVindex.Col)}})
		ins.Rows.(sqlparser.Values)[0] = append(ins.Rows.(sqlparser.Values)[0].(sqlparser.ValTuple), &sqlparser.NullVal{})
	}
	row := ins.Rows.(sqlparser.Values)[0].(sqlparser.ValTuple)
	val, err := asInterface(row[pos])
	if err != nil {
		return fmt.Errorf("could not convert val: %s, pos: %d: %v", sqlparser.String(row[pos]), pos, err)
	}
	plan.Values = append(plan.Values.([]interface{}), val)
	row[pos] = sqlparser.ValArg([]byte(fmt.Sprintf(":_%s", colVindex.Col)))
	return nil
}
Example #12
0
func findOrInsertPos(ins *sqlparser.Insert, col string) (row sqlparser.ValTuple, pos int) {
	pos = -1
	for i, column := range ins.Columns {
		if col == sqlparser.GetColName(column.(*sqlparser.NonStarExpr).Expr) {
			pos = i
			break
		}
	}
	if pos == -1 {
		pos = len(ins.Columns)
		ins.Columns = append(ins.Columns, &sqlparser.NonStarExpr{Expr: &sqlparser.ColName{Name: sqlparser.SQLName(col)}})
		ins.Rows.(sqlparser.Values)[0] = append(ins.Rows.(sqlparser.Values)[0].(sqlparser.ValTuple), &sqlparser.NullVal{})
	}
	return ins.Rows.(sqlparser.Values)[0].(sqlparser.ValTuple), pos
}
Example #13
0
// getWhereClause returns a whereClause based on desired upper and lower
// bounds for primary key.
func (qs *QuerySplitter) getWhereClause(whereClause *sqlparser.Where, bindVars map[string]interface{}, start, end sqltypes.Value) *sqlparser.Where {
	var startClause *sqlparser.ComparisonExpr
	var endClause *sqlparser.ComparisonExpr
	var clauses sqlparser.BoolExpr
	// No upper or lower bound, just return the where clause of original query
	if start.IsNull() && end.IsNull() {
		return whereClause
	}
	pk := &sqlparser.ColName{
		Name: sqlparser.SQLName(qs.splitColumn),
	}
	if !start.IsNull() {
		startClause = &sqlparser.ComparisonExpr{
			Operator: sqlparser.AST_GE,
			Left:     pk,
			Right:    sqlparser.ValArg([]byte(":" + startBindVarName)),
		}
		if start.IsNumeric() {
			v, _ := start.ParseInt64()
			bindVars[startBindVarName] = v
		} else if start.IsString() {
			bindVars[startBindVarName] = start.Raw()
		} else if start.IsFractional() {
			v, _ := start.ParseFloat64()
			bindVars[startBindVarName] = v
		}
	}
	// splitColumn < end
	if !end.IsNull() {
		endClause = &sqlparser.ComparisonExpr{
			Operator: sqlparser.AST_LT,
			Left:     pk,
			Right:    sqlparser.ValArg([]byte(":" + endBindVarName)),
		}
		if end.IsNumeric() {
			v, _ := end.ParseInt64()
			bindVars[endBindVarName] = v
		} else if end.IsString() {
			bindVars[endBindVarName] = end.Raw()
		} else if end.IsFractional() {
			v, _ := end.ParseFloat64()
			bindVars[endBindVarName] = v
		}
	}
	if startClause == nil {
		clauses = endClause
	} else {
		if endClause == nil {
			clauses = startClause
		} else {
			// splitColumn >= start AND splitColumn < end
			clauses = &sqlparser.AndExpr{
				Left:  startClause,
				Right: endClause,
			}
		}
	}
	if whereClause != nil {
		clauses = &sqlparser.AndExpr{
			Left:  &sqlparser.ParenBoolExpr{Expr: whereClause.Expr},
			Right: &sqlparser.ParenBoolExpr{Expr: clauses},
		}
	}
	return &sqlparser.Where{
		Type: sqlparser.AST_WHERE,
		Expr: clauses,
	}
}