// getDMLRouting updates the route with the necessary routing
// info. If it cannot find a unique route, then it returns an error.
func getDMLRouting(where *sqlparser.Where, route *engine.Route) error {
if where == nil {
return errors.New("unsupported: multi-shard where clause in DML")
}
for _, index := range route.Table.Ordered {
if !vindexes.IsUnique(index.Vindex) {
continue
}
if values := getMatch(where.Expr, index.Column); values != nil {
route.Vindex = index.Vindex
route.Values = values
return nil
}
}
return errors.New("unsupported: multi-shard where clause in DML")
}
// buildIndexPlan adds the insert value to the Values field for the specified ColVindex.
// This value will be used at the time of insert to validate the vindex value.
func buildIndexPlan(ins *sqlparser.Insert, colVindex *vindexes.ColVindex, route *engine.Route) error {
row, pos := findOrInsertPos(ins, colVindex.Col)
val, err := valConvert(row[pos])
if err != nil {
return fmt.Errorf("could not convert val: %s, pos: %d: %v", sqlparser.String(row[pos]), pos, err)
}
route.Values = append(route.Values.([]interface{}), val)
row[pos] = sqlparser.ValArg([]byte(":_" + colVindex.Col))
return nil
}
func buildAutoincPlan(ins *sqlparser.Insert, autoinc *vindexes.Autoinc, route *engine.Route) error {
route.Generate = &engine.Generate{
Opcode: engine.SelectUnsharded,
Keyspace: autoinc.Sequence.Keyspace,
Query: fmt.Sprintf("select next value from `%s`", autoinc.Sequence.Name),
}
// If it's also a colvindex, we have to add a redirect from route.Values.
// Otherwise, we have to redirect from row[pos].
if autoinc.ColVindexNum >= 0 {
route.Generate.Value = route.Values.([]interface{})[autoinc.ColVindexNum]
route.Values.([]interface{})[autoinc.ColVindexNum] = ":" + engine.SeqVarName
return nil
}
row, pos := findOrInsertPos(ins, autoinc.Col)
val, err := valConvert(row[pos])
if err != nil {
return fmt.Errorf("could not convert val: %s, pos: %d: %v", sqlparser.String(row[pos]), pos, err)
}
route.Generate.Value = val
row[pos] = sqlparser.ValArg([]byte(":" + engine.SeqVarName))
return nil
}