// ShowUsers returns all the users.
// Privileges: SELECT on system.users.
func (p *planner) ShowUsers(n *parser.ShowUsers) (planNode, error) {
stmt, err := parser.ParseOneTraditional(`SELECT username FROM system.users`)
if err != nil {
return nil, err
}
return p.newPlan(stmt, nil, true)
}
func initVirtualTableDesc(p *planner, t virtualSchemaTable) (sqlbase.TableDescriptor, error) {
stmt, err := parser.ParseOneTraditional(t.schema)
if err != nil {
return sqlbase.TableDescriptor{}, err
}
create := stmt.(*parser.CreateTable)
return p.makeTableDesc(create, 0, keys.VirtualDescriptorID, emptyPrivileges, nil)
}
// query initializes a planNode from a SQL statement string. Close() must be
// called on the returned planNode after use.
func (p *planner) query(sql string, args ...interface{}) (planNode, error) {
stmt, err := parser.ParseOneTraditional(sql)
if err != nil {
return nil, err
}
golangFillQueryArguments(p.semaCtx.Placeholders, args)
return p.makePlan(stmt, false)
}
// ShowDatabases returns all the databases.
// Privileges: None.
// Notes: postgres does not have a "show databases"
// mysql has a "SHOW DATABASES" permission, but we have no system-level permissions.
func (p *planner) ShowDatabases(n *parser.ShowDatabases) (planNode, error) {
const getDatabases = `SELECT SCHEMA_NAME AS "Database" FROM information_schema.schemata
ORDER BY "Database"`
stmt, err := parser.ParseOneTraditional(getDatabases)
if err != nil {
return nil, err
}
return p.newPlan(stmt, nil, true)
}
func TestMakeDatabaseDesc(t *testing.T) {
defer leaktest.AfterTest(t)()
stmt, err := parser.ParseOneTraditional("CREATE DATABASE test")
if err != nil {
t.Fatal(err)
}
desc := makeDatabaseDesc(stmt.(*parser.CreateDatabase))
if desc.Name != "test" {
t.Fatalf("expected Name == test, got %s", desc.Name)
}
// ID is not set yet.
if desc.ID != 0 {
t.Fatalf("expected ID == 0, got %d", desc.ID)
}
if len(desc.GetPrivileges().Users) != 1 {
t.Fatalf("wrong number of privilege users, expected 1, got: %d", len(desc.GetPrivileges().Users))
}
}
// getViewPlan builds a planDataSource for the view specified by the
// table name and descriptor, expanding out its subquery plan.
func (p *planner) getViewPlan(
tn *parser.TableName, desc *sqlbase.TableDescriptor,
) (planDataSource, error) {
// Parse the query as Traditional syntax because we know the query was
// saved in the descriptor by printing it with parser.Format.
stmt, err := parser.ParseOneTraditional(desc.ViewQuery)
if err != nil {
return planDataSource{}, errors.Wrapf(err, "failed to parse underlying query from view %q", tn)
}
sel, ok := stmt.(*parser.Select)
if !ok {
return planDataSource{},
errors.Errorf("failed to parse underlying query from view %q as a select", tn)
}
// When constructing the subquery plan, we don't want to check for the SELECT
// privilege on the underlying tables, just on the view itself. Checking on
// the underlying tables as well would defeat the purpose of having separate
// SELECT privileges on the view, which is intended to allow for exposing
// some subset of a restricted table's data to less privileged users.
if !p.skipSelectPrivilegeChecks {
if err := p.checkPrivilege(desc, privilege.SELECT); err != nil {
return planDataSource{}, err
}
p.skipSelectPrivilegeChecks = true
defer func() { p.skipSelectPrivilegeChecks = false }()
}
// TODO(a-robinson): Support ORDER BY and LIMIT in views. Is it as simple as
// just passing the entire select here or will inserting an ORDER BY in the
// middle of a query plan break things?
plan, err := p.getSubqueryPlan(sel.Select, makeResultColumns(desc.Columns))
if err != nil {
return plan, err
}
plan.info.viewDesc = desc
return plan, nil
}
// ShowCreateView returns a CREATE VIEW statement for the specified view in
// Traditional syntax.
// Privileges: Any privilege on view.
func (p *planner) ShowCreateView(n *parser.ShowCreateView) (planNode, error) {
tn, err := n.View.NormalizeWithDatabaseName(p.session.Database)
if err != nil {
return nil, err
}
desc, err := p.mustGetViewDesc(tn)
if err != nil {
return nil, err
}
if err := p.anyPrivilege(desc); err != nil {
return nil, err
}
columns := ResultColumns{
{Name: "View", Typ: parser.TypeString},
{Name: "CreateView", Typ: parser.TypeString},
}
return &delayedNode{
p: p,
name: "SHOW CREATE VIEW " + tn.String(),
columns: columns,
constructor: func(p *planner) (planNode, error) {
v := p.newContainerValuesNode(columns, 0)
var buf bytes.Buffer
fmt.Fprintf(&buf, "CREATE VIEW %s ", quoteNames(n.View.String()))
// Determine whether custom column names were specified when the view
// was created, and include them if so.
customColNames := false
stmt, err := parser.ParseOneTraditional(desc.ViewQuery)
if err != nil {
return nil, errors.Wrapf(err, "failed to parse underlying query from view %q", tn)
}
sel, ok := stmt.(*parser.Select)
if !ok {
return nil, errors.Errorf("failed to parse underlying query from view %q as a select", tn)
}
// When constructing the Select plan, make sure we don't require any
// privileges on the underlying tables.
p.skipSelectPrivilegeChecks = true
defer func() { p.skipSelectPrivilegeChecks = false }()
sourcePlan, err := p.Select(sel, []parser.Type{}, false)
if err != nil {
return nil, err
}
for i, col := range sourcePlan.Columns() {
if col.Name != desc.Columns[i].Name {
customColNames = true
break
}
}
if customColNames {
colNames := make([]string, 0, len(desc.Columns))
for _, col := range desc.Columns {
colNames = append(colNames, col.Name)
}
fmt.Fprintf(&buf, "(%s) ", strings.Join(colNames, ", "))
}
fmt.Fprintf(&buf, "AS %s", desc.ViewQuery)
if _, err := v.rows.AddRow(parser.DTuple{
parser.NewDString(n.View.String()),
parser.NewDString(buf.String()),
}); err != nil {
v.rows.Close()
return nil, err
}
return v, nil
},
}, nil
}
