// detachConditions distinguishs between access conditions and filter conditions from conditions.
func detachConditions(conditions []expression.Expression, table *model.TableInfo,
idx *model.IndexInfo, colOffset int) ([]expression.Expression, []expression.Expression) {
var pkName model.CIStr
var accessConditions, filterConditions []expression.Expression
if table.PKIsHandle {
for _, colInfo := range table.Columns {
if mysql.HasPriKeyFlag(colInfo.Flag) {
pkName = colInfo.Name
break
}
}
}
for _, con := range conditions {
if pkName.L != "" {
checker := conditionChecker{
tableName: table.Name,
pkName: pkName,
idx: idx,
columnOffset: colOffset}
if checker.newCheck(con) {
accessConditions = append(accessConditions, con)
continue
}
}
filterConditions = append(filterConditions, con)
}
return accessConditions, filterConditions
}
func (b *planBuilder) buildTableScanPlan(path *joinPath) Plan {
tn := path.table
p := &TableScan{
Table: tn.TableInfo,
TableName: tn,
}
// Equal condition contains a column from previous joined table.
p.RefAccess = len(path.eqConds) > 0
p.SetFields(tn.GetResultFields())
p.TableAsName = getTableAsName(p.Fields())
var pkName model.CIStr
if p.Table.PKIsHandle {
for _, colInfo := range p.Table.Columns {
if mysql.HasPriKeyFlag(colInfo.Flag) {
pkName = colInfo.Name
}
}
}
for _, con := range path.conditions {
if pkName.L != "" {
checker := conditionChecker{tableName: tn.TableInfo.Name, pkName: pkName}
if checker.check(con) {
p.AccessConditions = append(p.AccessConditions, con)
} else {
p.FilterConditions = append(p.FilterConditions, con)
}
} else {
p.FilterConditions = append(p.FilterConditions, con)
}
}
return p
}
// detachTableScanConditions distinguishes between access conditions and filter conditions from conditions.
func detachTableScanConditions(conditions []expression.Expression, table *model.TableInfo) ([]expression.Expression, []expression.Expression) {
var pkName model.CIStr
if table.PKIsHandle {
for _, colInfo := range table.Columns {
if mysql.HasPriKeyFlag(colInfo.Flag) {
pkName = colInfo.Name
break
}
}
}
if pkName.L == "" {
return nil, conditions
}
var accessConditions, filterConditions []expression.Expression
checker := conditionChecker{
tableName: table.Name,
pkName: pkName}
for _, cond := range conditions {
cond = pushDownNot(cond, false)
if !checker.newCheck(cond) {
filterConditions = append(filterConditions, cond)
continue
}
accessConditions = append(accessConditions, cond)
// TODO: it will lead to repeated compution cost.
if checker.shouldReserve {
filterConditions = append(filterConditions, cond)
checker.shouldReserve = false
}
}
return accessConditions, filterConditions
}
func (e *ShowExec) fetchShowIndex() error {
tb, err := e.getTable()
if err != nil {
return errors.Trace(err)
}
if tb.Meta().PKIsHandle {
var pkCol *table.Column
for _, col := range tb.Cols() {
if mysql.HasPriKeyFlag(col.Flag) {
pkCol = col
break
}
}
data := types.MakeDatums(
tb.Meta().Name.O, // Table
0, // Non_unique
"PRIMARY", // Key_name
1, // Seq_in_index
pkCol.Name.O, // Column_name
"utf8_bin", // Colation
0, // Cardinality
nil, // Sub_part
nil, // Packed
"", // Null
"BTREE", // Index_type
"", // Comment
"", // Index_comment
)
e.rows = append(e.rows, &Row{Data: data})
}
for _, idx := range tb.Indices() {
for i, col := range idx.Meta().Columns {
nonUniq := 1
if idx.Meta().Unique {
nonUniq = 0
}
var subPart interface{}
if col.Length != types.UnspecifiedLength {
subPart = col.Length
}
data := types.MakeDatums(
tb.Meta().Name.O, // Table
nonUniq, // Non_unique
idx.Meta().Name.O, // Key_name
i+1, // Seq_in_index
col.Name.O, // Column_name
"utf8_bin", // Colation
0, // Cardinality
subPart, // Sub_part
nil, // Packed
"YES", // Null
idx.Meta().Tp.String(), // Index_type
"", // Comment
idx.Meta().Comment, // Index_comment
)
e.rows = append(e.rows, &Row{Data: data})
}
}
return nil
}
func (b *planBuilder) buildTableScanPlan(tn *ast.TableName, conditions []ast.ExprNode) Plan {
p := &TableScan{
Table: tn.TableInfo,
}
p.SetFields(tn.GetResultFields())
var pkName model.CIStr
if p.Table.PKIsHandle {
for _, colInfo := range p.Table.Columns {
if mysql.HasPriKeyFlag(colInfo.Flag) {
pkName = colInfo.Name
}
}
}
for _, con := range conditions {
if pkName.L != "" {
checker := conditionChecker{tableName: tn.TableInfo.Name, pkName: pkName}
if checker.check(con) {
p.AccessConditions = append(p.AccessConditions, con)
} else {
p.FilterConditions = append(p.FilterConditions, con)
}
} else {
p.FilterConditions = append(p.FilterConditions, con)
}
}
return p
}
func (isp *InfoSchemaPlan) fetchStatisticsInTable(is infoschema.InfoSchema, schema *model.DBInfo, table *model.TableInfo) {
if table.PKIsHandle {
for _, col := range table.Columns {
if mysql.HasPriKeyFlag(col.Flag) {
record := []interface{}{
catalogVal, // TABLE_CATALOG
schema.Name.O, // TABLE_SCHEMA
table.Name.O, // TABLE_NAME
"0", // NON_UNIQUE
schema.Name.O, // INDEX_SCHEMA
"PRIMARY", // INDEX_NAME
1, // SEQ_IN_INDEX
col.Name.O, // COLUMN_NAME
"A", // COLLATION
0, // CARDINALITY
nil, // SUB_PART
nil, // PACKED
"", // NULLABLE
"BTREE", // INDEX_TYPE
"", // COMMENT
"", // INDEX_COMMENT
}
isp.rows = append(isp.rows, &plan.Row{Data: record})
}
}
}
for _, index := range table.Indices {
nonUnique := "1"
if index.Unique {
nonUnique = "0"
}
for i, key := range index.Columns {
col, _ := is.ColumnByName(schema.Name, table.Name, key.Name)
nullable := "YES"
if mysql.HasNotNullFlag(col.Flag) {
nullable = ""
}
record := []interface{}{
catalogVal, // TABLE_CATALOG
schema.Name.O, // TABLE_SCHEMA
table.Name.O, // TABLE_NAME
nonUnique, // NON_UNIQUE
schema.Name.O, // INDEX_SCHEMA
index.Name.O, // INDEX_NAME
i + 1, // SEQ_IN_INDEX
key.Name.O, // COLUMN_NAME
"A", // COLLATION
0, // CARDINALITY
nil, // SUB_PART
nil, // PACKED
nullable, // NULLABLE
"BTREE", // INDEX_TYPE
"", // COMMENT
"", // INDEX_COMMENT
}
isp.rows = append(isp.rows, &plan.Row{Data: record})
}
}
}
// matchOrder checks if the plan has the same ordering as items.
func matchOrder(p Plan, items []*ast.ByItem) bool {
switch x := p.(type) {
case *Aggregate:
return false
case *IndexScan:
if len(items) > len(x.Index.Columns) {
return false
}
for i, item := range items {
if item.Desc {
return false
}
var rf *ast.ResultField
switch y := item.Expr.(type) {
case *ast.ColumnNameExpr:
rf = y.Refer
case *ast.PositionExpr:
rf = y.Refer
default:
return false
}
if rf.Table.Name.L != x.Table.Name.L || rf.Column.Name.L != x.Index.Columns[i].Name.L {
return false
}
}
return true
case *TableScan:
if len(items) != 1 || !x.Table.PKIsHandle {
return false
}
if items[0].Desc {
return false
}
var refer *ast.ResultField
switch x := items[0].Expr.(type) {
case *ast.ColumnNameExpr:
refer = x.Refer
case *ast.PositionExpr:
refer = x.Refer
default:
return false
}
if mysql.HasPriKeyFlag(refer.Column.Flag) {
return true
}
return false
case *JoinOuter:
return false
case *JoinInner:
return false
case *Sort:
// Sort plan should not be checked here as there should only be one sort plan in a plan tree.
return false
case WithSrcPlan:
return matchOrder(x.Src(), items)
}
return true
}
func equivHasIndex(rf *ast.ResultField) bool {
if rf.Table.PKIsHandle && mysql.HasPriKeyFlag(rf.Column.Flag) {
return true
}
for _, idx := range rf.Table.Indices {
if len(idx.Columns) == 1 && idx.Columns[0].Name.L == rf.Column.Name.L {
return true
}
}
return false
}
// ColumnsToProto converts a slice of model.ColumnInfo to a slice of tipb.ColumnInfo.
func ColumnsToProto(columns []*model.ColumnInfo, pkIsHandle bool) []*tipb.ColumnInfo {
cols := make([]*tipb.ColumnInfo, 0, len(columns))
for _, c := range columns {
col := columnToProto(c)
if pkIsHandle && mysql.HasPriKeyFlag(c.Flag) {
col.PkHandle = true
} else {
col.PkHandle = false
}
cols = append(cols, col)
}
return cols
}
func (r *refiner) sortBypass(p *Sort) {
if r.indexScan != nil {
idx := r.indexScan.Index
if len(p.ByItems) > len(idx.Columns) {
return
}
var desc bool
for i, val := range p.ByItems {
if val.Desc {
desc = true
}
cn, ok := val.Expr.(*ast.ColumnNameExpr)
if !ok {
return
}
if r.indexScan.Table.Name.L != cn.Refer.Table.Name.L {
return
}
indexColumn := idx.Columns[i]
if indexColumn.Name.L != cn.Refer.Column.Name.L {
return
}
}
if desc {
// TODO: support desc when index reverse iterator is supported.
r.indexScan.Desc = true
return
}
p.Bypass = true
} else if r.tableScan != nil {
if len(p.ByItems) != 1 {
return
}
byItem := p.ByItems[0]
if byItem.Desc {
// TODO: support desc when table reverse iterator is supported.
return
}
cn, ok := byItem.Expr.(*ast.ColumnNameExpr)
if !ok {
return
}
if !mysql.HasPriKeyFlag(cn.Refer.Column.Flag) {
return
}
if !cn.Refer.Table.PKIsHandle {
return
}
p.Bypass = true
}
}
func (e *XSelectIndexExec) indexRowToTableRow(handle int64, indexRow []types.Datum) []types.Datum {
tableRow := make([]types.Datum, len(e.indexPlan.Columns))
for i, tblCol := range e.indexPlan.Columns {
if mysql.HasPriKeyFlag(tblCol.Flag) && e.indexPlan.Table.PKIsHandle {
tableRow[i] = types.NewIntDatum(handle)
continue
}
for j, idxCol := range e.indexPlan.Index.Columns {
if tblCol.Name.L == idxCol.Name.L {
tableRow[i] = indexRow[j]
break
}
}
}
return tableRow
}
// TableToProto converts a model.TableInfo to a tipb.TableInfo.
func TableToProto(t *model.TableInfo) *tipb.TableInfo {
pt := &tipb.TableInfo{
TableId: proto.Int64(t.ID),
}
cols := make([]*tipb.ColumnInfo, 0, len(t.Columns))
for _, c := range t.Columns {
col := columnToProto(c)
if t.PKIsHandle && mysql.HasPriKeyFlag(c.Flag) {
col.PkHandle = proto.Bool(true)
} else {
col.PkHandle = proto.Bool(false)
}
cols = append(cols, col)
}
pt.Columns = cols
return pt
}
func isCoveringIndex(columns []*model.ColumnInfo, indexColumns []*model.IndexColumn, pkIsHandle bool) bool {
for _, colInfo := range columns {
if pkIsHandle && mysql.HasPriKeyFlag(colInfo.Flag) {
continue
}
isIndexColumn := false
for _, indexCol := range indexColumns {
if colInfo.Name.L == indexCol.Name.L && indexCol.Length == types.UnspecifiedLength {
isIndexColumn = true
break
}
}
if !isIndexColumn {
return false
}
}
return true
}
// NewColDesc returns a new ColDesc for a column.
func NewColDesc(col *Column) *ColDesc {
// TODO: if we have no primary key and a unique index which's columns are all not null
// we will set these columns' flag as PriKeyFlag
// see https://dev.mysql.com/doc/refman/5.7/en/show-columns.html
// create table
name := col.Name
nullFlag := "YES"
if mysql.HasNotNullFlag(col.Flag) {
nullFlag = "NO"
}
keyFlag := ""
if mysql.HasPriKeyFlag(col.Flag) {
keyFlag = "PRI"
} else if mysql.HasUniKeyFlag(col.Flag) {
keyFlag = "UNI"
} else if mysql.HasMultipleKeyFlag(col.Flag) {
keyFlag = "MUL"
}
var defaultValue interface{}
if !mysql.HasNoDefaultValueFlag(col.Flag) {
defaultValue = col.DefaultValue
}
extra := ""
if mysql.HasAutoIncrementFlag(col.Flag) {
extra = "auto_increment"
} else if mysql.HasOnUpdateNowFlag(col.Flag) {
extra = "on update CURRENT_TIMESTAMP"
}
return &ColDesc{
Field: name.O,
Type: col.GetTypeDesc(),
Collation: col.Collate,
Null: nullFlag,
Key: keyFlag,
DefaultValue: defaultValue,
Extra: extra,
Privileges: defaultPrivileges,
Comment: "",
}
}
func detachIndexFilterConditions(conditions []expression.Expression, indexColumns []*model.IndexColumn, table *model.TableInfo) ([]expression.Expression, []expression.Expression) {
var pKName model.CIStr
if table.PKIsHandle {
for _, colInfo := range table.Columns {
if mysql.HasPriKeyFlag(colInfo.Flag) {
pKName = colInfo.Name
break
}
}
}
var indexConditions, tableConditions []expression.Expression
for _, cond := range conditions {
if checkIndexCondition(cond, indexColumns, pKName) {
indexConditions = append(indexConditions, cond)
} else {
tableConditions = append(tableConditions, cond)
}
}
return indexConditions, tableConditions
}
func (r *refiner) buildTableRange(p *TableScan) {
var pkHandleColumn *model.ColumnInfo
for _, colInfo := range p.Table.Columns {
if mysql.HasPriKeyFlag(colInfo.Flag) && p.Table.PKIsHandle {
pkHandleColumn = colInfo
}
}
if pkHandleColumn == nil {
return
}
rb := rangeBuilder{}
rangePoints := fullRange
checker := conditionChecker{pkName: pkHandleColumn.Name, tableName: p.Table.Name}
for _, cond := range r.conditions {
if checker.check(cond) {
rangePoints = rb.intersection(rangePoints, rb.build(cond))
}
}
p.Ranges = rb.buildTableRanges(rangePoints)
r.err = rb.err
}
// IndexToProto converts a model.IndexInfo to a tipb.IndexInfo.
func IndexToProto(t *model.TableInfo, idx *model.IndexInfo) *tipb.IndexInfo {
pi := &tipb.IndexInfo{
TableId: t.ID,
IndexId: idx.ID,
Unique: idx.Unique,
}
cols := make([]*tipb.ColumnInfo, 0, len(idx.Columns)+1)
for _, c := range idx.Columns {
cols = append(cols, columnToProto(t.Columns[c.Offset]))
}
if t.PKIsHandle {
// Coprocessor needs to know PKHandle column info, so we need to append it.
for _, col := range t.Columns {
if mysql.HasPriKeyFlag(col.Flag) {
colPB := columnToProto(col)
colPB.PkHandle = true
cols = append(cols, colPB)
break
}
}
}
pi.Columns = cols
return pi
}
func (e *ShowExec) fetchShowCreateTable() error {
tb, err := e.getTable()
if err != nil {
return errors.Trace(err)
}
// TODO: let the result more like MySQL.
var buf bytes.Buffer
buf.WriteString(fmt.Sprintf("CREATE TABLE `%s` (\n", tb.Meta().Name.O))
var pkCol *table.Column
for i, col := range tb.Cols() {
buf.WriteString(fmt.Sprintf(" `%s` %s", col.Name.O, col.GetTypeDesc()))
if mysql.HasAutoIncrementFlag(col.Flag) {
buf.WriteString(" NOT NULL AUTO_INCREMENT")
} else {
if mysql.HasNotNullFlag(col.Flag) {
buf.WriteString(" NOT NULL")
}
if !mysql.HasNoDefaultValueFlag(col.Flag) {
switch col.DefaultValue {
case nil:
buf.WriteString(" DEFAULT NULL")
case "CURRENT_TIMESTAMP":
buf.WriteString(" DEFAULT CURRENT_TIMESTAMP")
default:
buf.WriteString(fmt.Sprintf(" DEFAULT '%v'", col.DefaultValue))
}
}
if mysql.HasOnUpdateNowFlag(col.Flag) {
buf.WriteString(" ON UPDATE CURRENT_TIMESTAMP")
}
}
if len(col.Comment) > 0 {
buf.WriteString(fmt.Sprintf(" COMMENT '%s'", col.Comment))
}
if i != len(tb.Cols())-1 {
buf.WriteString(",\n")
}
if tb.Meta().PKIsHandle && mysql.HasPriKeyFlag(col.Flag) {
pkCol = col
}
}
if pkCol != nil {
// If PKIsHanle, pk info is not in tb.Indices(). We should handle it here.
buf.WriteString(",\n")
buf.WriteString(fmt.Sprintf(" PRIMARY KEY (`%s`)", pkCol.Name.O))
}
if len(tb.Indices()) > 0 || len(tb.Meta().ForeignKeys) > 0 {
buf.WriteString(",\n")
}
for i, idx := range tb.Indices() {
idxInfo := idx.Meta()
if idxInfo.Primary {
buf.WriteString(" PRIMARY KEY ")
} else if idxInfo.Unique {
buf.WriteString(fmt.Sprintf(" UNIQUE KEY `%s` ", idxInfo.Name.O))
} else {
buf.WriteString(fmt.Sprintf(" KEY `%s` ", idxInfo.Name.O))
}
cols := make([]string, 0, len(idxInfo.Columns))
for _, c := range idxInfo.Columns {
cols = append(cols, c.Name.O)
}
buf.WriteString(fmt.Sprintf("(`%s`)", strings.Join(cols, "`,`")))
if i != len(tb.Indices())-1 {
buf.WriteString(",\n")
}
}
if len(tb.Indices()) > 0 && len(tb.Meta().ForeignKeys) > 0 {
buf.WriteString(",\n")
}
for _, fk := range tb.Meta().ForeignKeys {
if fk.State != model.StatePublic {
continue
}
cols := make([]string, 0, len(fk.Cols))
for _, c := range fk.Cols {
cols = append(cols, c.O)
}
refCols := make([]string, 0, len(fk.RefCols))
for _, c := range fk.Cols {
refCols = append(refCols, c.O)
}
buf.WriteString(fmt.Sprintf(" CONSTRAINT `%s` FOREIGN KEY (`%s`)", fk.Name.O, strings.Join(cols, "`,`")))
buf.WriteString(fmt.Sprintf(" REFERENCES `%s` (`%s`)", fk.RefTable.O, strings.Join(refCols, "`,`")))
if ast.ReferOptionType(fk.OnDelete) != ast.ReferOptionNoOption {
buf.WriteString(fmt.Sprintf(" ON DELETE %s", ast.ReferOptionType(fk.OnDelete)))
}
if ast.ReferOptionType(fk.OnUpdate) != ast.ReferOptionNoOption {
buf.WriteString(fmt.Sprintf(" ON UPDATE %s", ast.ReferOptionType(fk.OnUpdate)))
}
}
buf.WriteString("\n")
buf.WriteString(") ENGINE=InnoDB")
if s := tb.Meta().Charset; len(s) > 0 {
buf.WriteString(fmt.Sprintf(" DEFAULT CHARSET=%s", s))
}
if tb.Meta().AutoIncID > 0 {
buf.WriteString(fmt.Sprintf(" AUTO_INCREMENT=%d", tb.Meta().AutoIncID))
}
if len(tb.Meta().Comment) > 0 {
buf.WriteString(fmt.Sprintf(" COMMENT='%s'", tb.Meta().Comment))
}
data := types.MakeDatums(tb.Meta().Name.O, buf.String())
e.rows = append(e.rows, &Row{Data: data})
return nil
}
func dataForStatisticsInTable(schema *model.DBInfo, table *model.TableInfo) [][]types.Datum {
rows := [][]types.Datum{}
if table.PKIsHandle {
for _, col := range table.Columns {
if mysql.HasPriKeyFlag(col.Flag) {
record := types.MakeDatums(
catalogVal, // TABLE_CATALOG
schema.Name.O, // TABLE_SCHEMA
table.Name.O, // TABLE_NAME
"0", // NON_UNIQUE
schema.Name.O, // INDEX_SCHEMA
"PRIMARY", // INDEX_NAME
1, // SEQ_IN_INDEX
col.Name.O, // COLUMN_NAME
"A", // COLLATION
0, // CARDINALITY
nil, // SUB_PART
nil, // PACKED
"", // NULLABLE
"BTREE", // INDEX_TYPE
"", // COMMENT
"", // INDEX_COMMENT
)
rows = append(rows, record)
}
}
}
nameToCol := make(map[string]*model.ColumnInfo, len(table.Columns))
for _, c := range table.Columns {
nameToCol[c.Name.L] = c
}
for _, index := range table.Indices {
nonUnique := "1"
if index.Unique {
nonUnique = "0"
}
for i, key := range index.Columns {
col := nameToCol[key.Name.L]
nullable := "YES"
if mysql.HasNotNullFlag(col.Flag) {
nullable = ""
}
record := types.MakeDatums(
catalogVal, // TABLE_CATALOG
schema.Name.O, // TABLE_SCHEMA
table.Name.O, // TABLE_NAME
nonUnique, // NON_UNIQUE
schema.Name.O, // INDEX_SCHEMA
index.Name.O, // INDEX_NAME
i+1, // SEQ_IN_INDEX
key.Name.O, // COLUMN_NAME
"A", // COLLATION
0, // CARDINALITY
nil, // SUB_PART
nil, // PACKED
nullable, // NULLABLE
"BTREE", // INDEX_TYPE
"", // COMMENT
"", // INDEX_COMMENT
)
rows = append(rows, record)
}
}
return rows
}
func (p *DataSource) handleTableScan(prop requiredProperty) (*physicalPlanInfo, *physicalPlanInfo, error) {
table := p.Table
var resultPlan PhysicalPlan
ts := &PhysicalTableScan{
Table: p.Table,
Columns: p.Columns,
TableAsName: p.TableAsName,
DBName: p.DBName,
}
ts.SetSchema(p.GetSchema())
resultPlan = ts
if sel, ok := p.GetParentByIndex(0).(*Selection); ok {
newSel := *sel
conds := make([]expression.Expression, 0, len(sel.Conditions))
for _, cond := range sel.Conditions {
conds = append(conds, cond.DeepCopy())
}
ts.AccessCondition, newSel.Conditions = detachTableScanConditions(conds, table)
err := buildNewTableRange(ts)
if err != nil {
return nil, nil, errors.Trace(err)
}
if len(newSel.Conditions) > 0 {
newSel.SetChildren(ts)
resultPlan = &newSel
}
} else {
ts.Ranges = []TableRange{{math.MinInt64, math.MaxInt64}}
}
statsTbl := p.statisticTable
rowCount := uint64(statsTbl.Count)
if table.PKIsHandle {
for i, colInfo := range ts.Columns {
if mysql.HasPriKeyFlag(colInfo.Flag) {
ts.pkCol = p.GetSchema()[i]
break
}
}
var offset int
for _, colInfo := range table.Columns {
if mysql.HasPriKeyFlag(colInfo.Flag) {
offset = colInfo.Offset
break
}
}
rowCount = 0
for _, rg := range ts.Ranges {
var cnt int64
var err error
if rg.LowVal == math.MinInt64 && rg.HighVal == math.MaxInt64 {
cnt = statsTbl.Count
} else if rg.LowVal == math.MinInt64 {
cnt, err = statsTbl.Columns[offset].LessRowCount(types.NewDatum(rg.HighVal))
} else if rg.HighVal == math.MaxInt64 {
cnt, err = statsTbl.Columns[offset].GreaterRowCount(types.NewDatum(rg.LowVal))
} else {
cnt, err = statsTbl.Columns[offset].BetweenRowCount(types.NewDatum(rg.LowVal), types.NewDatum(rg.HighVal))
}
if err != nil {
return nil, nil, errors.Trace(err)
}
rowCount += uint64(cnt)
}
}
rowCounts := []uint64{rowCount}
return resultPlan.matchProperty(prop, rowCounts), resultPlan.matchProperty(nil, rowCounts), nil
}
// IsPKHandleColumn checks if the column is primary key handle column.
func (c *Column) IsPKHandleColumn(tbInfo *model.TableInfo) bool {
return mysql.HasPriKeyFlag(c.Flag) && tbInfo.PKIsHandle
}
func (p *DataSource) convert2TableScan(prop *requiredProperty) (*physicalPlanInfo, error) {
client := p.ctx.GetClient()
ts := &PhysicalTableScan{
Table: p.Table,
Columns: p.Columns,
TableAsName: p.TableAsName,
DBName: p.DBName,
physicalTableSource: physicalTableSource{client: client},
}
ts.tp = Tbl
ts.allocator = p.allocator
ts.SetSchema(p.GetSchema())
ts.initIDAndContext(p.ctx)
txn, err := p.ctx.GetTxn(false)
if err != nil {
return nil, errors.Trace(err)
}
if txn != nil {
ts.readOnly = txn.IsReadOnly()
} else {
ts.readOnly = true
}
var resultPlan PhysicalPlan
resultPlan = ts
table := p.Table
sc := p.ctx.GetSessionVars().StmtCtx
if sel, ok := p.GetParentByIndex(0).(*Selection); ok {
newSel := *sel
conds := make([]expression.Expression, 0, len(sel.Conditions))
for _, cond := range sel.Conditions {
conds = append(conds, cond.Clone())
}
ts.AccessCondition, newSel.Conditions = detachTableScanConditions(conds, table)
memDB := infoschema.IsMemoryDB(p.DBName.L)
isDistReq := !memDB && client != nil && client.SupportRequestType(kv.ReqTypeSelect, 0)
if isDistReq {
ts.TableConditionPBExpr, ts.tableFilterConditions, newSel.Conditions =
expressionsToPB(sc, newSel.Conditions, client)
}
err := buildTableRange(ts)
if err != nil {
return nil, errors.Trace(err)
}
if len(newSel.Conditions) > 0 {
newSel.SetChildren(ts)
newSel.onTable = true
resultPlan = &newSel
}
} else {
ts.Ranges = []TableRange{{math.MinInt64, math.MaxInt64}}
}
statsTbl := p.statisticTable
rowCount := uint64(statsTbl.Count)
if table.PKIsHandle {
for i, colInfo := range ts.Columns {
if mysql.HasPriKeyFlag(colInfo.Flag) {
ts.pkCol = p.GetSchema()[i]
break
}
}
var offset int
for _, colInfo := range table.Columns {
if mysql.HasPriKeyFlag(colInfo.Flag) {
offset = colInfo.Offset
break
}
}
rowCount, err = getRowCountByTableRange(sc, statsTbl, ts.Ranges, offset)
if err != nil {
return nil, errors.Trace(err)
}
}
if ts.TableConditionPBExpr != nil {
rowCount = uint64(float64(rowCount) * selectionFactor)
}
return resultPlan.matchProperty(prop, &physicalPlanInfo{count: rowCount}), nil
}
// pushOrder tries to push order by items to the plan, returns true if
// order is pushed.
func pushOrder(p Plan, items []*ast.ByItem) bool {
switch x := p.(type) {
case *Aggregate:
return false
case *IndexScan:
if len(items) > len(x.Index.Columns) {
return false
}
var hasDesc bool
var hasAsc bool
for i, item := range items {
var rf *ast.ResultField
switch y := item.Expr.(type) {
case *ast.ColumnNameExpr:
rf = y.Refer
case *ast.PositionExpr:
rf = y.Refer
default:
return false
}
if rf.Table.Name.L != x.Table.Name.L || rf.Column.Name.L != x.Index.Columns[i].Name.L {
return false
}
if item.Desc {
if hasAsc {
return false
}
hasDesc = true
} else {
if hasDesc {
return false
}
hasAsc = true
}
}
x.Desc = hasDesc
return true
case *TableScan:
if len(items) != 1 || !x.Table.PKIsHandle {
return false
}
var refer *ast.ResultField
switch x := items[0].Expr.(type) {
case *ast.ColumnNameExpr:
refer = x.Refer
case *ast.PositionExpr:
refer = x.Refer
default:
return false
}
if mysql.HasPriKeyFlag(refer.Column.Flag) {
x.Desc = items[0].Desc
return true
}
return false
case *JoinOuter:
return false
case *JoinInner:
return false
case *Sort:
// Sort plan should not be checked here as there should only be one sort plan in a plan tree.
return false
default:
child := x.GetChildByIndex(0)
if child != nil {
return pushOrder(child, items)
}
}
return false
}
func (p *DataSource) convert2TableScan(prop *requiredProperty) (*physicalPlanInfo, error) {
table := p.Table
client := p.ctx.GetClient()
txn, err := p.ctx.GetTxn(false)
if err != nil {
return nil, errors.Trace(err)
}
var resultPlan PhysicalPlan
ts := &PhysicalTableScan{
Table: p.Table,
Columns: p.Columns,
TableAsName: p.TableAsName,
DBName: p.DBName,
physicalTableSource: physicalTableSource{client: client},
}
if txn != nil {
ts.readOnly = txn.IsReadOnly()
} else {
ts.readOnly = true
}
ts.SetSchema(p.GetSchema())
resultPlan = ts
if sel, ok := p.GetParentByIndex(0).(*Selection); ok {
ts.conditions = sel.Conditions
newSel := *sel
conds := make([]expression.Expression, 0, len(sel.Conditions))
for _, cond := range sel.Conditions {
conds = append(conds, cond.Clone())
}
ts.AccessCondition, newSel.Conditions = detachTableScanConditions(conds, table)
if client != nil {
var memDB bool
switch p.DBName.L {
case "information_schema", "performance_schema":
memDB = true
}
if !memDB && client.SupportRequestType(kv.ReqTypeSelect, 0) {
ts.ConditionPBExpr, newSel.Conditions = expressionsToPB(newSel.Conditions, client)
}
}
err := buildTableRange(ts)
if err != nil {
return nil, errors.Trace(err)
}
if len(newSel.Conditions) > 0 {
newSel.SetChildren(ts)
newSel.onTable = true
resultPlan = &newSel
}
} else {
ts.Ranges = []TableRange{{math.MinInt64, math.MaxInt64}}
}
statsTbl := p.statisticTable
rowCount := uint64(statsTbl.Count)
if table.PKIsHandle {
for i, colInfo := range ts.Columns {
if mysql.HasPriKeyFlag(colInfo.Flag) {
ts.pkCol = p.GetSchema()[i]
break
}
}
var offset int
for _, colInfo := range table.Columns {
if mysql.HasPriKeyFlag(colInfo.Flag) {
offset = colInfo.Offset
break
}
}
rowCount = 0
for _, rg := range ts.Ranges {
var cnt int64
var err error
if rg.LowVal == math.MinInt64 && rg.HighVal == math.MaxInt64 {
cnt = statsTbl.Count
} else if rg.LowVal == math.MinInt64 {
cnt, err = statsTbl.Columns[offset].LessRowCount(types.NewDatum(rg.HighVal))
} else if rg.HighVal == math.MaxInt64 {
cnt, err = statsTbl.Columns[offset].GreaterRowCount(types.NewDatum(rg.LowVal))
} else {
cnt, err = statsTbl.Columns[offset].BetweenRowCount(types.NewDatum(rg.LowVal), types.NewDatum(rg.HighVal))
}
if err != nil {
return nil, errors.Trace(err)
}
rowCount += uint64(cnt)
}
}
if ts.ConditionPBExpr != nil {
rowCount = uint64(float64(rowCount) * selectionFactor)
}
return resultPlan.matchProperty(prop, &physicalPlanInfo{count: rowCount}), nil
}
