// ShowIndex returns all the indexes for a table.
// Privileges: None.
// Notes: postgres does not have a SHOW INDEX statement.
// mysql requires some privilege for any column.
func (p *planner) ShowIndex(n *parser.ShowIndex) (planNode, error) {
desc, err := p.getTableDesc(n.Table)
if err != nil {
return nil, err
}
v := &valuesNode{columns: []string{"Table", "Name", "Unique", "Seq", "Column", "Storing"}}
name := n.Table.Table()
for _, index := range append([]IndexDescriptor{desc.PrimaryIndex}, desc.Indexes...) {
j := 1
for i, cols := range [][]string{index.ColumnNames, index.StoreColumnNames} {
for _, col := range cols {
v.rows = append(v.rows, []parser.Datum{
parser.DString(name),
parser.DString(index.Name),
parser.DBool(index.Unique),
parser.DInt(j),
parser.DString(col),
parser.DBool(i == 1),
})
j++
}
}
}
return v, nil
}
func (vals *debugValues) AsRow() parser.DTuple {
keyVal := parser.DNull
if vals.key != "" {
keyVal = parser.DString(vals.key)
}
// The "output" value is NULL for partial rows, or a DBool indicating if the row passed the
// filtering.
outputVal := parser.DNull
switch vals.output {
case debugValueFiltered:
outputVal = parser.DBool(false)
case debugValueRow:
outputVal = parser.DBool(true)
}
return parser.DTuple{
parser.DInt(vals.rowIdx),
keyVal,
parser.DString(vals.value),
outputVal,
}
}
func checkEquivExpr(a, b parser.Expr, qvals qvalMap) error {
// The expressions above only use the values 1 and 2. Verify that the
// simplified expressions evaluate to the same value as the original
// expression for interesting values.
zero := parser.DInt(0)
for _, v := range []parser.Datum{zero, zero + 1, zero + 2, zero + 3, parser.DNull} {
for _, q := range qvals {
q.datum = v
}
da, err := a.Eval(parser.EvalContext{})
if err != nil {
return fmt.Errorf("%s: %v", a, err)
}
db, err := b.Eval(parser.EvalContext{})
if err != nil {
return fmt.Errorf("%s: %v", b, err)
}
// This is tricky: we don't require the expressions to produce identical
// results, but to either both return true or both return not true (either
// false or NULL).
if (da == parser.DBool(true)) != (db == parser.DBool(true)) {
return fmt.Errorf("%s: %s: expected %s, but found %s", a, v, da, db)
}
}
return nil
}
func makeNot(expr parser.Expr) parser.Expr {
if expr == parser.DBool(true) {
return parser.DBool(false)
}
if expr == parser.DBool(false) {
return parser.DBool(true)
}
return &parser.NotExpr{Expr: expr}
}
func simplifyNotExpr(n *parser.NotExpr) parser.Expr {
switch t := n.Expr.(type) {
case *parser.ComparisonExpr:
op := t.Operator
switch op {
case parser.EQ:
op = parser.NE
case parser.NE:
op = parser.EQ
case parser.GT:
op = parser.LE
case parser.GE:
op = parser.LT
case parser.LT:
op = parser.GE
case parser.LE:
op = parser.GT
case parser.In:
op = parser.NotIn
case parser.NotIn:
op = parser.In
case parser.Like:
op = parser.NotLike
case parser.NotLike:
op = parser.Like
case parser.SimilarTo:
op = parser.NotSimilarTo
case parser.NotSimilarTo:
op = parser.SimilarTo
default:
return parser.DBool(true)
}
return simplifyExpr(&parser.ComparisonExpr{
Operator: op,
Left: t.Left,
Right: t.Right,
})
case *parser.AndExpr:
// De Morgan's Law: NOT (a AND b) -> (NOT a) OR (NOT b)
return simplifyExpr(&parser.OrExpr{
Left: &parser.NotExpr{Expr: t.Left},
Right: &parser.NotExpr{Expr: t.Right},
})
case *parser.OrExpr:
// De Morgan's Law: NOT (a OR b) -> (NOT a) AND (NOT b)
return simplifyExpr(&parser.AndExpr{
Left: &parser.NotExpr{Expr: t.Left},
Right: &parser.NotExpr{Expr: t.Right},
})
}
return parser.DBool(true)
}
func makeOr(left parser.Expr, right parser.Expr) parser.Expr {
if left == parser.DBool(true) || right == parser.DBool(true) {
return parser.DBool(true)
}
if left == parser.DBool(false) {
return right
}
if right == parser.DBool(false) {
return left
}
return &parser.OrExpr{Left: left, Right: right}
}
// ShowIndex returns all the indexes for a table.
// Privileges: Any privilege on table.
// Notes: postgres does not have a SHOW INDEXES statement.
// mysql requires some privilege for any column.
func (p *planner) ShowIndex(n *parser.ShowIndex) (planNode, error) {
tn, err := n.Table.NormalizeWithDatabaseName(p.session.Database)
if err != nil {
return nil, err
}
desc, err := p.mustGetTableDesc(tn)
if err != nil {
return nil, err
}
if err := p.anyPrivilege(desc); err != nil {
return nil, err
}
v := &valuesNode{
columns: []ResultColumn{
{Name: "Table", Typ: parser.TypeString},
{Name: "Name", Typ: parser.TypeString},
{Name: "Unique", Typ: parser.TypeBool},
{Name: "Seq", Typ: parser.TypeInt},
{Name: "Column", Typ: parser.TypeString},
{Name: "Direction", Typ: parser.TypeString},
{Name: "Storing", Typ: parser.TypeBool},
},
}
appendRow := func(index sqlbase.IndexDescriptor, colName string, sequence int,
direction string, isStored bool) {
v.rows = append(v.rows, []parser.Datum{
parser.NewDString(tn.Table()),
parser.NewDString(index.Name),
parser.MakeDBool(parser.DBool(index.Unique)),
parser.NewDInt(parser.DInt(sequence)),
parser.NewDString(colName),
parser.NewDString(direction),
parser.MakeDBool(parser.DBool(isStored)),
})
}
for _, index := range append([]sqlbase.IndexDescriptor{desc.PrimaryIndex}, desc.Indexes...) {
sequence := 1
for i, col := range index.ColumnNames {
appendRow(index, col, sequence, index.ColumnDirections[i].String(), false)
sequence++
}
for _, col := range index.StoreColumnNames {
appendRow(index, col, sequence, "N/A", true)
sequence++
}
}
return v, nil
}
// splitFilter splits a boolean expression E into two boolean expressions RES and REM such that:
//
// - RES contains only variables known to the conversion function (it is "restricted" to a
// particular set of variables). These variables are also converted as returned by conv.
//
// - the original expression is equivalent to the conjunction (AND) between the RES and REM
// expressions.
//
// Splitting allows us to do filtering at various layers, where one layer only knows the values of
// some variables. Instead of evaluating E in an upper layer, we evaluate RES in a lower layer
// and then evaluate REM in the upper layer (on results that passed the RES filter).
//
// Notes:
// - the implementation is best-effort (it tries to get as much of the expression into RES as
// possible, and make REM as small as possible).
// - the original expression is modified in-place and should not be used again.
func splitFilter(expr parser.Expr, conv varConvertFunc) (restricted, remainder parser.Expr) {
if expr == nil {
return nil, nil
}
restricted, remainder = splitBoolExpr(expr, conv, true)
if restricted == parser.DBool(true) {
restricted = nil
}
if remainder == parser.DBool(true) {
remainder = nil
}
return restricted, remainder
}
func simplifyComparisonExpr(n *parser.ComparisonExpr) parser.Expr {
// NormalizeExpr will have left comparisons in the form "<var> <op>
// <datum>" unless they could not be simplified further in which case
// simplifyExpr cannot handle them. For example, "lower(a) = 'foo'"
if isVar(n.Left) && isDatum(n.Right) {
// All of the comparison operators have the property that when comparing to
// NULL they evaulate to NULL (see evalComparisonOp). NULL is not the same
// as false, but in the context of a WHERE clause, NULL is considered
// not-true which is the same as false.
if n.Right == parser.DNull {
return parser.DBool(false)
}
switch n.Operator {
case parser.EQ, parser.NE, parser.GT, parser.GE, parser.LT, parser.LE:
return n
case parser.In, parser.NotIn:
tuple, ok := n.Right.(parser.DTuple)
if !ok {
break
}
if !typeCheckTuple(n.Left, tuple) {
break
}
sort.Sort(tuple)
tuple = uniqTuple(tuple)
if len(tuple) == 0 {
return parser.DBool(false)
}
n.Right = tuple
return n
case parser.Like:
// a LIKE 'foo%' -> a >= "foo" AND a < "fop"
if d, ok := n.Right.(parser.DString); ok {
if i := strings.IndexAny(string(d), "_%"); i >= 0 {
return makePrefixRange(d[:i], n.Left, false)
}
return makePrefixRange(d, n.Left, true)
}
case parser.SimilarTo:
// a SIMILAR TO "foo.*" -> a >= "foo" AND a < "fop"
if d, ok := n.Right.(parser.DString); ok {
if re, err := regexp.Compile(string(d)); err == nil {
prefix, complete := re.LiteralPrefix()
return makePrefixRange(parser.DString(prefix), n.Left, complete)
}
}
}
}
return parser.DBool(true)
}
func (v *applyConstraintsVisitor) VisitPost(expr parser.Expr) parser.Expr {
switch t := expr.(type) {
case *parser.AndExpr:
if t.Left == parser.DBool(true) && t.Right == parser.DBool(true) {
return parser.DBool(true)
} else if t.Left == parser.DBool(true) {
return t.Right
} else if t.Right == parser.DBool(true) {
return t.Left
}
}
return expr
}
func simplifyOneOrInExpr(left, right *parser.ComparisonExpr) (parser.Expr, parser.Expr) {
if left.Operator != parser.In && right.Operator != parser.In {
panic(fmt.Sprintf("IN expression required: %s vs %s", left, right))
}
switch left.Operator {
case parser.EQ:
switch right.Operator {
case parser.In:
left, right = right, left
}
fallthrough
case parser.In:
tuple, ok := left.Right.(parser.DTuple)
if !ok {
return parser.DBool(true), nil
}
var tuple2 parser.DTuple
switch right.Operator {
case parser.EQ:
rdatum, rok := right.Right.(parser.Datum)
if !rok {
return parser.DBool(true), nil
}
tuple2 = parser.DTuple{rdatum}
case parser.In:
tuple2, ok = right.Right.(parser.DTuple)
if !ok {
return parser.DBool(true), nil
}
}
if !typeCheckTuple(left.Left, tuple2) {
return left, right
}
// We keep the tuples for an in expression in sorted order. So now we just
// merge the two sorted lists.
return &parser.ComparisonExpr{
Operator: parser.In,
Left: left.Left,
Right: mergeSorted(tuple, tuple2),
}, nil
}
return left, right
}
// Arg implements the parser.Args interface.
func (p parameters) Arg(name string) (parser.Datum, bool) {
i, err := processPositionalArgument(name)
if err != nil {
return nil, false
}
if i < 1 || int(i) > len(p) {
return nil, false
}
arg := p[i-1].Payload
if arg == nil {
return parser.DNull, true
}
switch t := arg.(type) {
case *driver.Datum_BoolVal:
return parser.DBool(t.BoolVal), true
case *driver.Datum_IntVal:
return parser.DInt(t.IntVal), true
case *driver.Datum_FloatVal:
return parser.DFloat(t.FloatVal), true
case *driver.Datum_BytesVal:
return parser.DBytes(t.BytesVal), true
case *driver.Datum_StringVal:
return parser.DString(t.StringVal), true
case *driver.Datum_DateVal:
return parser.DDate(t.DateVal), true
case *driver.Datum_TimeVal:
return parser.DTimestamp{Time: t.TimeVal.GoTime()}, true
case *driver.Datum_IntervalVal:
return parser.DInterval{Duration: time.Duration(t.IntervalVal)}, true
default:
panic(fmt.Sprintf("unexpected type %T", t))
}
}
// ShowColumns of a table.
// Privileges: None.
// Notes: postgres does not have a SHOW COLUMNS statement.
// mysql only returns columns you have privileges on.
func (p *planner) ShowColumns(n *parser.ShowColumns) (planNode, error) {
desc, err := p.getTableDesc(n.Table)
if err != nil {
return nil, err
}
if desc == nil {
return nil, sqlbase.NewUndefinedTableError(n.Table.String())
}
v := &valuesNode{
columns: []ResultColumn{
{Name: "Field", Typ: parser.TypeString},
{Name: "Type", Typ: parser.TypeString},
{Name: "Null", Typ: parser.TypeBool},
{Name: "Default", Typ: parser.TypeString},
},
}
for i, col := range desc.Columns {
defaultExpr := parser.Datum(parser.DNull)
if e := desc.Columns[i].DefaultExpr; e != nil {
defaultExpr = parser.NewDString(*e)
}
v.rows = append(v.rows, []parser.Datum{
parser.NewDString(desc.Columns[i].Name),
parser.NewDString(col.Type.SQLString()),
parser.MakeDBool(parser.DBool(desc.Columns[i].Nullable)),
defaultExpr,
})
}
return v, nil
}
func (n *scanNode) unmarshalValue(kv client.KeyValue) (parser.Datum, bool) {
kind, ok := n.colKind[n.colID]
if !ok {
n.err = fmt.Errorf("column-id \"%d\" does not exist", n.colID)
return nil, false
}
if kv.Exists() {
switch kind {
case ColumnType_INT:
return parser.DInt(kv.ValueInt()), true
case ColumnType_BOOL:
return parser.DBool(kv.ValueInt() != 0), true
case ColumnType_FLOAT:
return parser.DFloat(math.Float64frombits(uint64(kv.ValueInt()))), true
case ColumnType_STRING, ColumnType_BYTES:
return parser.DString(kv.ValueBytes()), true
case ColumnType_DATE:
var t time.Time
if err := t.UnmarshalBinary(kv.ValueBytes()); err != nil {
return nil, false
}
return parser.DDate{Time: t}, true
case ColumnType_TIMESTAMP:
var t time.Time
if err := t.UnmarshalBinary(kv.ValueBytes()); err != nil {
return nil, false
}
return parser.DTimestamp{Time: t}, true
case ColumnType_INTERVAL:
return parser.DInterval{Duration: time.Duration(kv.ValueInt())}, true
}
}
return parser.DNull, true
}
// applyConstraints applies the constraints on values specified by constraints
// to an expression, simplifying the expression where possible. For example, if
// the expression is "a = 1" and the constraint is "a = 1", the expression can
// be simplified to "true". If the expression is "a = 1 AND b > 2" and the
// constraint is "a = 1", the expression is simplified to "b > 2".
//
// Note that applyConstraints currently only handles simple cases.
func applyConstraints(expr parser.Expr, constraints indexConstraints) parser.Expr {
v := &applyConstraintsVisitor{}
for _, c := range constraints {
v.constraint = c
expr = parser.WalkExpr(v, expr)
// We can only continue to apply the constraints if the constraints we have
// applied so far are equality constraints. There are two cases to
// consider: the first is that both the start and end constraints are
// equality.
if c.start == c.end {
if c.start.Operator == parser.EQ {
continue
}
// The second case is that both the start and end constraint are an IN
// operator with only a single value.
if c.start.Operator == parser.In && len(c.start.Right.(parser.DTuple)) == 1 {
continue
}
}
break
}
if expr == parser.DBool(true) {
return nil
}
return expr
}
// applyConstraints applies the constraints on values specified by constraints
// to an expression, simplifying the expression where possible. For example, if
// the expression is "a = 1" and the constraint is "a = 1", the expression can
// be simplified to "true". If the expression is "a = 1 AND b > 2" and the
// constraint is "a = 1", the expression is simplified to "b > 2".
//
// Note that applyConstraints currently only handles simple cases.
func applyConstraints(expr parser.Expr, constraints orIndexConstraints) parser.Expr {
if len(constraints) != 1 {
// We only support simplifying the expressions if there aren't multiple
// disjunctions (top-level OR branches).
return expr
}
v := &applyConstraintsVisitor{}
for _, c := range constraints[0] {
v.constraint = c
expr, _ = parser.WalkExpr(v, expr)
// We can only continue to apply the constraints if the constraints we have
// applied so far are equality constraints. There are two cases to
// consider: the first is that both the start and end constraints are
// equality.
if c.start == c.end {
if c.start.Operator == parser.EQ {
continue
}
// The second case is that both the start and end constraint are an IN
// operator with only a single value.
if c.start.Operator == parser.In && len(c.start.Right.(parser.DTuple)) == 1 {
continue
}
}
break
}
if expr == parser.DBool(true) {
return nil
}
return expr
}
func decodeTableKey(valType parser.Datum, key []byte) (parser.Datum, []byte, error) {
var isNull bool
if key, isNull = encoding.DecodeIfNull(key); isNull {
return parser.DNull, key, nil
}
switch valType.(type) {
case parser.DBool:
rkey, i, err := encoding.DecodeVarint(key)
return parser.DBool(i != 0), rkey, err
case parser.DInt:
rkey, i, err := encoding.DecodeVarint(key)
return parser.DInt(i), rkey, err
case parser.DFloat:
rkey, f, err := encoding.DecodeFloat(key, nil)
return parser.DFloat(f), rkey, err
case parser.DString:
rkey, r, err := encoding.DecodeString(key, nil)
return parser.DString(r), rkey, err
case parser.DBytes:
rkey, r, err := encoding.DecodeString(key, nil)
return parser.DBytes(r), rkey, err
case parser.DDate:
rkey, t, err := encoding.DecodeTime(key)
return parser.DDate{Time: t}, rkey, err
case parser.DTimestamp:
rkey, t, err := encoding.DecodeTime(key)
return parser.DTimestamp{Time: t}, rkey, err
case parser.DInterval:
rkey, d, err := encoding.DecodeVarint(key)
return parser.DInterval{Duration: time.Duration(d)}, rkey, err
default:
return nil, nil, util.Errorf("TODO(pmattis): decoded index key: %s", valType.Type())
}
}
func datumFromProto(d driver.Datum) parser.Datum {
arg := d.Payload
if arg == nil {
return parser.DNull
}
switch t := arg.(type) {
case *driver.Datum_BoolVal:
return parser.DBool(t.BoolVal)
case *driver.Datum_IntVal:
return parser.DInt(t.IntVal)
case *driver.Datum_FloatVal:
return parser.DFloat(t.FloatVal)
case *driver.Datum_DecimalVal:
dec, err := decimal.NewFromString(t.DecimalVal)
if err != nil {
panic(fmt.Sprintf("could not parse decimal: %v", err))
}
return parser.DDecimal{Decimal: dec}
case *driver.Datum_BytesVal:
return parser.DBytes(t.BytesVal)
case *driver.Datum_StringVal:
return parser.DString(t.StringVal)
case *driver.Datum_DateVal:
return parser.DDate(t.DateVal)
case *driver.Datum_TimeVal:
return parser.DTimestamp{Time: t.TimeVal.GoTime()}
case *driver.Datum_IntervalVal:
return parser.DInterval{Duration: time.Duration(t.IntervalVal)}
default:
panic(fmt.Sprintf("unexpected type %T", t))
}
}
func decodeTableKey(valType parser.Datum, key []byte) (parser.Datum, []byte, error) {
var isNull bool
if key, isNull = encoding.DecodeIfNull(key); isNull {
return parser.DNull, key, nil
}
switch valType.(type) {
case parser.DBool:
var i int64
key, i = encoding.DecodeVarint(key)
return parser.DBool(i != 0), key, nil
case parser.DInt:
var i int64
key, i = encoding.DecodeVarint(key)
return parser.DInt(i), key, nil
case parser.DFloat:
var f float64
key, f = encoding.DecodeFloat(key, nil)
return parser.DFloat(f), key, nil
case parser.DString:
var r string
key, r = encoding.DecodeString(key, nil)
return parser.DString(r), key, nil
default:
return nil, nil, util.Errorf("TODO(pmattis): decoded index key: %s", valType.Type())
}
}
// explainDebug fills in four extra debugging values in the current row:
// - the row index,
// - the key,
// - a value string,
// - a true bool if we are at the end of the row, or a NULL otherwise.
func (n *scanNode) explainDebug(endOfRow bool) {
if len(n.row) == len(n.visibleCols) {
n.row = append(n.row, nil, nil, nil, nil)
}
debugVals := n.row[len(n.row)-4:]
debugVals[0] = parser.DInt(n.rowIndex)
debugVals[1] = parser.DString(n.prettyKey())
if n.implicitVals != nil {
debugVals[2] = parser.DString(prettyDatums(n.implicitVals))
} else {
// This conversion to DString is odd. `n.explainValue` is already a
// `Datum`, but logic_test currently expects EXPLAIN DEBUG output
// to come out formatted using `encodeSQLString`. This is not
// consistent across all printing of strings in logic_test, though.
// TODO(tamird/pmattis): figure out a consistent story for string
// printing in logic_test.
debugVals[2] = parser.DString(n.explainValue.String())
}
if endOfRow {
debugVals[3] = parser.DBool(true)
n.rowIndex++
} else {
debugVals[3] = parser.DNull
}
n.explainValue = nil
}
func (n *scanNode) explainDebug(endOfRow, outputRow bool) {
if n.row == nil {
n.row = make([]parser.Datum, len(n.columns))
}
n.row[0] = parser.DInt(n.rowIndex)
n.row[1] = parser.DString(n.prettyKey())
if n.implicitVals != nil {
n.row[2] = parser.DString(prettyKeyVals(n.implicitVals))
} else {
// This conversion to DString is odd. `n.explainValue` is already a
// `Datum`, but logic_test currently expects EXPLAIN DEBUG output
// to come out formatted using `encodeSQLString`. This is not
// consistent across all printing of strings in logic_test, though.
// TODO(tamird/pmattis): figure out a consistent story for string
// printing in logic_test.
n.row[2] = parser.DString(n.explainValue.String())
}
if endOfRow {
n.row[3] = parser.DBool(outputRow)
n.rowIndex++
} else {
n.row[3] = parser.DNull
}
n.explainValue = nil
}
func datumFromProto(d driver.Datum) parser.Datum {
arg := d.Payload
if arg == nil {
return parser.DNull
}
switch t := arg.(type) {
case *driver.Datum_BoolVal:
return parser.DBool(t.BoolVal)
case *driver.Datum_IntVal:
return parser.DInt(t.IntVal)
case *driver.Datum_FloatVal:
return parser.DFloat(t.FloatVal)
case *driver.Datum_DecimalVal:
dd := &parser.DDecimal{}
if _, ok := dd.SetString(t.DecimalVal); !ok {
panic(fmt.Sprintf("could not parse string %q as decimal", t.DecimalVal))
}
return dd
case *driver.Datum_BytesVal:
return parser.DBytes(t.BytesVal)
case *driver.Datum_StringVal:
return parser.DString(t.StringVal)
case *driver.Datum_DateVal:
return parser.DDate(t.DateVal)
case *driver.Datum_TimeVal:
return parser.DTimestamp{Time: t.TimeVal.GoTime()}
case *driver.Datum_IntervalVal:
return parser.DInterval{Duration: time.Duration(t.IntervalVal)}
default:
panic(fmt.Sprintf("unexpected type %T", t))
}
}
func (n *scanNode) getQVal(col ColumnDescriptor) parser.Expr {
if n.qvals == nil {
n.qvals = make(qvalMap)
}
qval := n.qvals[col.ID]
if qval == nil {
qval = &qvalue{col: col}
// We initialize the qvalue expression to a datum of the type matching the
// column. This allows type analysis to be performed on the expression
// before we start retrieving rows.
//
// TODO(pmattis): Nullable columns can have NULL values. The type analysis
// needs to take that into consideration, but how to surface that info?
switch col.Type.Kind {
case ColumnType_BIT, ColumnType_INT:
qval.datum = parser.DInt(0)
case ColumnType_BOOL:
qval.datum = parser.DBool(true)
case ColumnType_FLOAT:
qval.datum = parser.DFloat(0)
case ColumnType_CHAR, ColumnType_TEXT,
ColumnType_BLOB:
qval.datum = parser.DString("")
default:
panic(fmt.Sprintf("unsupported column type: %s", col.Type.Kind))
}
n.qvals[col.ID] = qval
}
return qval
}
// Arg implements the Args interface
func (p parameters) Arg(name string) (parser.Datum, bool) {
if !unicode.IsDigit(rune(name[0])) {
// TODO(pmattis): Add support for named parameters (vs the numbered
// parameter support below).
return nil, false
}
i, err := strconv.ParseInt(name, 10, 0)
if err != nil {
return nil, false
}
if i < 1 || int(i) > len(p) {
return nil, false
}
arg := p[i-1].GetValue()
if arg == nil {
return parser.DNull, true
}
switch t := arg.(type) {
case *bool:
return parser.DBool(*t), true
case *int64:
return parser.DInt(*t), true
case *float64:
return parser.DFloat(*t), true
case []byte:
return parser.DString(t), true
case *string:
return parser.DString(*t), true
default:
panic(fmt.Sprintf("unexpected type %T", t))
}
}
// ShowColumns of a table.
// Privileges: None.
// Notes: postgres does not have a SHOW COLUMNS statement.
// mysql only returns columns you have privileges on.
func (p *planner) ShowColumns(n *parser.ShowColumns) (planNode, *roachpb.Error) {
desc, pErr := p.getTableDesc(n.Table)
if pErr != nil {
return nil, pErr
}
v := &valuesNode{
columns: []column{
{name: "Field", typ: parser.DummyString},
{name: "Type", typ: parser.DummyString},
{name: "Null", typ: parser.DummyBool},
{name: "Default", typ: parser.DummyString},
},
}
for i, col := range desc.Columns {
defaultExpr := parser.Datum(parser.DNull)
if e := desc.Columns[i].DefaultExpr; e != nil {
defaultExpr = parser.DString(*e)
}
v.rows = append(v.rows, []parser.Datum{
parser.DString(desc.Columns[i].Name),
parser.DString(col.Type.SQLString()),
parser.DBool(desc.Columns[i].Nullable),
defaultExpr,
})
}
return v, nil
}
// DecodeTableValue decodes a value encoded by EncodeTableValue.
func DecodeTableValue(a *DatumAlloc, valType parser.Datum, b []byte) (parser.Datum, []byte, error) {
// TODO(dan): Merge this and DecodeTableKey.
if len(b) == 0 {
return nil, nil, util.Errorf("empty slice")
}
if roachpb.ValueType(b[0]) == roachpb.ValueType_NULL {
return parser.DNull, b[1:], nil
}
var err error
switch valType.(type) {
case *parser.DBool:
var i int64
b, i, err = roachpb.DecodeIntValue(b)
// No need to chunk allocate DBool as MakeDBool returns either
// parser.DBoolTrue or parser.DBoolFalse.
return parser.MakeDBool(parser.DBool(i != 0)), b, err
case *parser.DInt:
var i int64
b, i, err = roachpb.DecodeIntValue(b)
return a.NewDInt(parser.DInt(i)), b, err
case *parser.DFloat:
var f float64
b, f, err = roachpb.DecodeFloatValue(b)
return a.NewDFloat(parser.DFloat(f)), b, err
case *parser.DDecimal:
var d *inf.Dec
b, d, err = roachpb.DecodeDecimalValue(b)
dd := a.NewDDecimal(parser.DDecimal{})
dd.Set(d)
return dd, b, err
case *parser.DString:
var data []byte
b, data, err = roachpb.DecodeBytesValue(b)
return a.NewDString(parser.DString(data)), b, err
case *parser.DBytes:
var data []byte
b, data, err = roachpb.DecodeBytesValue(b)
return a.NewDBytes(parser.DBytes(data)), b, err
case *parser.DDate:
var i int64
b, i, err = roachpb.DecodeIntValue(b)
return a.NewDDate(parser.DDate(i)), b, err
case *parser.DTimestamp:
var t time.Time
b, t, err = roachpb.DecodeTimeValue(b)
return a.NewDTimestamp(parser.DTimestamp{Time: t}), b, err
case *parser.DTimestampTZ:
var t time.Time
b, t, err = roachpb.DecodeTimeValue(b)
return a.NewDTimestampTZ(parser.DTimestampTZ{Time: t}), b, err
case *parser.DInterval:
var d duration.Duration
b, d, err = roachpb.DecodeDurationValue(b)
return a.NewDInterval(parser.DInterval{Duration: d}), b, err
default:
return nil, nil, util.Errorf("TODO(pmattis): decoded index value: %s", valType.Type())
}
}
// unmarshalColumnValue decodes the value from a key-value pair using the type
// expected by the column. An error is returned if the value's type does not
// match the column's type.
func unmarshalColumnValue(kind ColumnType_Kind, value *proto.Value) (parser.Datum, error) {
if value == nil {
return parser.DNull, nil
}
switch kind {
case ColumnType_BOOL:
v, err := value.GetInt()
if err != nil {
return nil, err
}
return parser.DBool(v != 0), nil
case ColumnType_INT:
v, err := value.GetInt()
if err != nil {
return nil, err
}
return parser.DInt(v), nil
case ColumnType_FLOAT:
v, err := value.GetFloat()
if err != nil {
return nil, err
}
return parser.DFloat(v), nil
case ColumnType_STRING:
v, err := value.GetBytesChecked()
if err != nil {
return nil, err
}
return parser.DString(v), nil
case ColumnType_BYTES:
v, err := value.GetBytesChecked()
if err != nil {
return nil, err
}
return parser.DBytes(v), nil
case ColumnType_DATE:
v, err := value.GetTime()
if err != nil {
return nil, err
}
return parser.DDate{Time: v}, nil
case ColumnType_TIMESTAMP:
v, err := value.GetTime()
if err != nil {
return nil, err
}
return parser.DTimestamp{Time: v}, nil
case ColumnType_INTERVAL:
v, err := value.GetInt()
if err != nil {
return nil, err
}
return parser.DInterval{Duration: time.Duration(v)}, nil
default:
return nil, util.Errorf("unsupported column type: %s", kind)
}
}
// golangFillQueryArguments populates the placeholder map with
// types and values from an array of Go values.
// TODO: This does not support arguments of the SQL 'Date' type, as there is not
// an equivalent type in Go's standard library. It's not currently needed by any
// of our internal tables.
func golangFillQueryArguments(pinfo *parser.PlaceholderInfo, args []interface{}) {
pinfo.Clear()
for i, arg := range args {
k := fmt.Sprint(i + 1)
if arg == nil {
pinfo.SetValue(k, parser.DNull)
continue
}
// A type switch to handle a few explicit types with special semantics:
// - Datums are passed along as is.
// - Time datatypes get special representation in the database.
var d parser.Datum
switch t := arg.(type) {
case parser.Datum:
d = t
case time.Time:
d = parser.MakeDTimestamp(t, time.Microsecond)
case time.Duration:
d = &parser.DInterval{Duration: duration.Duration{Nanos: t.Nanoseconds()}}
case *inf.Dec:
dd := &parser.DDecimal{}
dd.Set(t)
d = dd
}
if d == nil {
// Handle all types which have an underlying type that can be stored in the
// database.
// Note: if this reflection becomes a performance concern in the future,
// commonly used types could be added explicitly into the type switch above
// for a performance gain.
val := reflect.ValueOf(arg)
switch val.Kind() {
case reflect.Bool:
d = parser.MakeDBool(parser.DBool(val.Bool()))
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
d = parser.NewDInt(parser.DInt(val.Int()))
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
d = parser.NewDInt(parser.DInt(val.Uint()))
case reflect.Float32, reflect.Float64:
d = parser.NewDFloat(parser.DFloat(val.Float()))
case reflect.String:
d = parser.NewDString(val.String())
case reflect.Slice:
// Handle byte slices.
if val.Type().Elem().Kind() == reflect.Uint8 {
d = parser.NewDBytes(parser.DBytes(val.Bytes()))
}
}
if d == nil {
panic(fmt.Sprintf("unexpected type %T", arg))
}
}
pinfo.SetValue(k, d)
}
}
// DecodeTableValue decodes a value encoded by EncodeTableValue.
func DecodeTableValue(a *DatumAlloc, valType parser.Datum, b []byte) (parser.Datum, []byte, error) {
_, dataOffset, _, typ, err := encoding.DecodeValueTag(b)
if err != nil {
return nil, b, err
}
if typ == encoding.Null {
return parser.DNull, b[dataOffset:], nil
}
switch valType.(type) {
case *parser.DBool:
var x bool
b, x, err = encoding.DecodeBoolValue(b)
// No need to chunk allocate DBool as MakeDBool returns either
// parser.DBoolTrue or parser.DBoolFalse.
return parser.MakeDBool(parser.DBool(x)), b, err
case *parser.DInt:
var i int64
b, i, err = encoding.DecodeIntValue(b)
return a.NewDInt(parser.DInt(i)), b, err
case *parser.DFloat:
var f float64
b, f, err = encoding.DecodeFloatValue(b)
return a.NewDFloat(parser.DFloat(f)), b, err
case *parser.DDecimal:
var d *inf.Dec
b, d, err = encoding.DecodeDecimalValue(b)
dd := a.NewDDecimal(parser.DDecimal{})
dd.Set(d)
return dd, b, err
case *parser.DString:
var data []byte
b, data, err = encoding.DecodeBytesValue(b)
return a.NewDString(parser.DString(data)), b, err
case *parser.DBytes:
var data []byte
b, data, err = encoding.DecodeBytesValue(b)
return a.NewDBytes(parser.DBytes(data)), b, err
case *parser.DDate:
var i int64
b, i, err = encoding.DecodeIntValue(b)
return a.NewDDate(parser.DDate(i)), b, err
case *parser.DTimestamp:
var t time.Time
b, t, err = encoding.DecodeTimeValue(b)
return a.NewDTimestamp(parser.DTimestamp{Time: t}), b, err
case *parser.DTimestampTZ:
var t time.Time
b, t, err = encoding.DecodeTimeValue(b)
return a.NewDTimestampTZ(parser.DTimestampTZ{Time: t}), b, err
case *parser.DInterval:
var d duration.Duration
b, d, err = encoding.DecodeDurationValue(b)
return a.NewDInterval(parser.DInterval{Duration: d}), b, err
default:
return nil, nil, errors.Errorf("TODO(pmattis): decoded index value: %s", valType.Type())
}
}
// ShowIndex returns all the indexes for a table.
// Privileges: None.
// Notes: postgres does not have a SHOW INDEX statement.
// mysql requires some privilege for any column.
func (p *planner) ShowIndex(n *parser.ShowIndex) (planNode, *roachpb.Error) {
desc, pErr := p.getTableDesc(n.Table)
if pErr != nil {
return nil, pErr
}
v := &valuesNode{
columns: []column{
{name: "Table", typ: parser.DummyString},
{name: "Name", typ: parser.DummyString},
{name: "Unique", typ: parser.DummyBool},
{name: "Seq", typ: parser.DummyInt},
{name: "Column", typ: parser.DummyString},
{name: "Direction", typ: parser.DummyString},
{name: "Storing", typ: parser.DummyBool},
},
}
appendRow := func(index IndexDescriptor, colName string, sequence int,
direction string, isStored bool) {
v.rows = append(v.rows, []parser.Datum{
parser.DString(n.Table.Table()),
parser.DString(index.Name),
parser.DBool(index.Unique),
parser.DInt(sequence),
parser.DString(colName),
parser.DString(direction),
parser.DBool(isStored),
})
}
for _, index := range append([]IndexDescriptor{desc.PrimaryIndex}, desc.Indexes...) {
sequence := 1
for i, col := range index.ColumnNames {
appendRow(index, col, sequence, index.ColumnDirections[i].String(), false)
sequence++
}
for _, col := range index.StoreColumnNames {
appendRow(index, col, sequence, "N/A", true)
sequence++
}
}
return v, nil
}
