func (r *JoinPlan) findMatchedRows(ctx context.Context, row *plan.Row, p plan.Plan, right bool) (err error) {
r.cursor = 0
r.matchedRows = nil
p.Close()
for {
var cmpRow *plan.Row
cmpRow, err = p.Next(ctx)
if err != nil {
return errors.Trace(err)
}
if cmpRow == nil {
break
}
// Do append(s1, s2) safely. Sometime the s1 capability is larger than its real length, so
// multi append may overwrite last valid data, e.g,
// s1 = make([]interface{}, 0, 1)
// s = append(s1, []interface{}{1})
// ss = append(ss, s)
// s = append(s1, []interface{}{2})
// ss = append(ss, s)
// We will see that ss only contains 2.
joined := make([]interface{}, 0, len(cmpRow.Data)+len(row.Data))
if right {
joined = append(append(joined, cmpRow.Data...), row.Data...)
} else {
joined = append(append(joined, row.Data...), cmpRow.Data...)
}
r.evalArgs[expression.ExprEvalIdentFunc] = func(name string) (interface{}, error) {
return GetIdentValue(name, r.Fields, joined, field.DefaultFieldFlag)
}
var b bool
b, err = expression.EvalBoolExpr(ctx, r.On, r.evalArgs)
if err != nil {
return errors.Trace(err)
}
if b {
cmpRow.Data = joined
keys := make([]*plan.RowKeyEntry, 0, len(row.RowKeys)+len(cmpRow.RowKeys))
cmpRow.RowKeys = append(append(keys, row.RowKeys...), cmpRow.RowKeys...)
r.matchedRows = append(r.matchedRows, cmpRow)
}
}
if len(r.matchedRows) == 0 {
if right {
leftLen := len(r.Fields) - len(r.Right.GetFields())
row.Data = append(make([]interface{}, leftLen), row.Data...)
} else {
rightLen := len(r.Fields) - len(r.Left.GetFields())
row.Data = append(row.Data, make([]interface{}, rightLen)...)
}
r.matchedRows = append(r.matchedRows, row)
}
return nil
}
func (r *JoinPlan) findMatchedRows(ctx context.Context, row *plan.Row, right bool) (err error) {
var p plan.Plan
if right {
p = r.Left
} else {
p = r.Right
}
r.cursor = 0
r.matchedRows = nil
p.Close()
for {
var cmpRow *plan.Row
cmpRow, err = p.Next(ctx)
if err != nil {
return errors.Trace(err)
}
if cmpRow == nil {
break
}
var joined []interface{}
if right {
joined = append(cmpRow.Data, row.Data...)
} else {
joined = append(row.Data, cmpRow.Data...)
}
r.evalArgs[expressions.ExprEvalIdentFunc] = func(name string) (interface{}, error) {
return GetIdentValue(name, r.Fields, joined, field.DefaultFieldFlag)
}
var b bool
b, err = expressions.EvalBoolExpr(ctx, r.On, r.evalArgs)
if err != nil {
return errors.Trace(err)
}
if b {
cmpRow.Data = joined
cmpRow.RowKeys = append(row.RowKeys, cmpRow.RowKeys...)
r.matchedRows = append(r.matchedRows, cmpRow)
}
}
if len(r.matchedRows) == 0 {
if right {
leftLen := len(r.Fields) - len(r.Right.GetFields())
row.Data = append(make([]interface{}, leftLen), row.Data...)
} else {
rightLen := len(r.Fields) - len(r.Left.GetFields())
row.Data = append(row.Data, make([]interface{}, rightLen)...)
}
r.matchedRows = append(r.matchedRows, row)
}
return nil
}