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query_result.go
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query_result.go
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// Copyright 2021 Matrix Origin
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package frontend
import (
"context"
"encoding/json"
"fmt"
"strings"
"time"
"github.com/google/uuid"
"go.uber.org/zap"
"github.com/matrixorigin/matrixone/pkg/catalog"
"github.com/matrixorigin/matrixone/pkg/common/moerr"
"github.com/matrixorigin/matrixone/pkg/common/mpool"
"github.com/matrixorigin/matrixone/pkg/container/batch"
"github.com/matrixorigin/matrixone/pkg/container/types"
"github.com/matrixorigin/matrixone/pkg/container/vector"
"github.com/matrixorigin/matrixone/pkg/defines"
"github.com/matrixorigin/matrixone/pkg/fileservice"
"github.com/matrixorigin/matrixone/pkg/frontend/constant"
"github.com/matrixorigin/matrixone/pkg/objectio"
"github.com/matrixorigin/matrixone/pkg/pb/plan"
"github.com/matrixorigin/matrixone/pkg/sql/parsers/tree"
"github.com/matrixorigin/matrixone/pkg/vm/engine/tae/blockio"
)
func getQueryResultDir() string {
return fileservice.JoinPath(defines.SharedFileServiceName, "/query_result")
}
func getPathOfQueryResultFile(fileName string) string {
return fmt.Sprintf("%s/%s", getQueryResultDir(), fileName)
}
func openSaveQueryResult(ctx context.Context, ses *Session) bool {
if ses.ast == nil || ses.tStmt == nil {
return false
}
if ses.tStmt.SqlSourceType == constant.InternalSql {
return false
}
if ses.tStmt.StatementType == "Select" && ses.tStmt.SqlSourceType != constant.CloudUserSql {
return false
}
val, err := ses.GetGlobalVar(ctx, "save_query_result")
if err != nil {
return false
}
if v, _ := val.(int8); v > 0 {
if ses.blockIdx == 0 {
if err = initQueryResulConfig(ctx, ses); err != nil {
return false
}
}
return true
}
return false
}
func initQueryResulConfig(ctx context.Context, ses *Session) error {
val, err := ses.GetGlobalVar(ctx, "query_result_maxsize")
if err != nil {
return err
}
switch v := val.(type) {
case uint64:
ses.limitResultSize = float64(v)
case float64:
ses.limitResultSize = v
}
var p uint64
val, err = ses.GetGlobalVar(ctx, "query_result_timeout")
if err != nil {
return err
}
switch v := val.(type) {
case uint64:
p = v
case float64:
p = uint64(v)
}
ses.createdTime = time.Now()
ses.expiredTime = ses.createdTime.Add(time.Hour * time.Duration(p))
return err
}
func saveQueryResult(ctx context.Context, ses *Session, bat *batch.Batch) error {
s := ses.curResultSize + float64(bat.Size())/(1024*1024)
if s > ses.limitResultSize {
logInfo(ses, ses.GetDebugString(), "open save query result", zap.Float64("current result size:", s))
return nil
}
fs := getGlobalPu().FileService
// write query result
path := catalog.BuildQueryResultPath(ses.GetTenantInfo().GetTenant(), uuid.UUID(ses.tStmt.StatementID).String(), ses.GetIncBlockIdx())
logInfo(ses, ses.GetDebugString(), "open save query result", zap.String("statemant id is:", uuid.UUID(ses.tStmt.StatementID).String()), zap.String("fileservice name is:", fs.Name()), zap.String("write path is:", path), zap.Float64("current result size:", s))
writer, err := objectio.NewObjectWriterSpecial(objectio.WriterQueryResult, path, fs)
if err != nil {
return err
}
_, err = writer.Write(bat)
if err != nil {
return err
}
option := objectio.WriteOptions{
Type: objectio.WriteTS,
Val: ses.expiredTime,
}
_, err = writer.WriteEnd(ctx, option)
if err != nil {
return err
}
ses.curResultSize = s
return err
}
func saveQueryResultMeta(ctx context.Context, ses *Session) error {
defer func() {
ses.ResetBlockIdx()
ses.p = nil
// TIPs: Session.SetTStmt() do reset the tStmt while query is DONE.
// Be careful, if you want to do async op.
ses.tStmt = nil
ses.curResultSize = 0
}()
fs := getGlobalPu().FileService
// write query result meta
colMap, err := buildColumnMap(ctx, ses.rs)
if err != nil {
return err
}
b, err := ses.rs.Marshal()
if err != nil {
return err
}
buf := new(strings.Builder)
prefix := ",\n"
for i := 1; i <= ses.blockIdx; i++ {
if i > 1 {
buf.WriteString(prefix)
}
buf.WriteString(catalog.BuildQueryResultPath(ses.GetTenantInfo().GetTenant(), uuid.UUID(ses.tStmt.StatementID).String(), i))
}
var sp []byte
if ses.p != nil {
sp, err = ses.p.Marshal()
if err != nil {
return err
}
}
st, err := simpleAstMarshal(ses.ast)
if err != nil {
return err
}
m := &catalog.Meta{
QueryId: ses.tStmt.StatementID,
Statement: ses.tStmt.Statement,
AccountId: ses.GetTenantInfo().GetTenantID(),
RoleId: ses.tStmt.RoleId,
ResultPath: buf.String(),
CreateTime: types.UnixToTimestamp(ses.createdTime.Unix()),
ResultSize: ses.curResultSize,
Columns: string(b),
Tables: getTablesFromPlan(ses.p),
UserId: ses.GetTenantInfo().GetUserID(),
ExpiredTime: types.UnixToTimestamp(ses.expiredTime.Unix()),
Plan: string(sp),
Ast: string(st),
ColumnMap: colMap,
}
metaBat, err := buildQueryResultMetaBatch(m, ses.pool)
if err != nil {
return err
}
metaPath := catalog.BuildQueryResultMetaPath(ses.GetTenantInfo().GetTenant(), uuid.UUID(ses.tStmt.StatementID).String())
metaWriter, err := objectio.NewObjectWriterSpecial(objectio.WriterQueryResult, metaPath, fs)
if err != nil {
return err
}
_, err = metaWriter.Write(metaBat)
if err != nil {
return err
}
option := objectio.WriteOptions{
Type: objectio.WriteTS,
Val: ses.expiredTime,
}
_, err = metaWriter.WriteEnd(ctx, option)
if err != nil {
return err
}
return err
}
func buildColumnMap(ctx context.Context, rs *plan.ResultColDef) (string, error) {
if rs == nil {
return "", moerr.NewInternalError(ctx, "resultColDef is nil")
}
m := make(map[string][]int)
org := make([]string, len(rs.ResultCols))
for i, col := range rs.ResultCols {
org[i] = col.Name
v := m[col.Name]
m[col.Name] = append(v, i)
}
for _, v := range m {
if len(v) > 1 {
for i := range v {
rs.ResultCols[v[i]].Name = fmt.Sprintf("%s_%d", rs.ResultCols[v[i]].Name, i)
}
}
}
buf := new(strings.Builder)
for i := range org {
if i > 0 {
buf.WriteString(", ")
}
if len(rs.ResultCols[i].Typ.Table) > 0 {
buf.WriteString(fmt.Sprintf("%s.%s -> %s", rs.ResultCols[i].Typ.Table, org[i], rs.ResultCols[i].Name))
} else {
buf.WriteString(fmt.Sprintf("%s -> %s", org[i], rs.ResultCols[i].Name))
}
}
return buf.String(), nil
}
func isResultQuery(p *plan.Plan) []string {
var uuids []string = nil
if q, ok := p.Plan.(*plan.Plan_Query); ok {
for _, n := range q.Query.Nodes {
if n.NodeType == plan.Node_EXTERNAL_SCAN {
if n.TableDef.TableType == "query_result" {
uuids = append(uuids, n.TableDef.Name)
}
} else if n.NodeType == plan.Node_FUNCTION_SCAN {
if n.TableDef.TblFunc.Name == "meta_scan" {
uuids = append(uuids, n.TableDef.Name)
}
}
}
}
return uuids
}
func checkPrivilege(uuids []string, reqCtx context.Context, ses *Session) error {
f := getGlobalPu().FileService
for _, id := range uuids {
// var size int64 = -1
path := catalog.BuildQueryResultMetaPath(ses.GetTenantInfo().GetTenant(), id)
reader, err := blockio.NewFileReader(f, path)
if err != nil {
return err
}
idxs := []uint16{catalog.PLAN_IDX, catalog.AST_IDX}
bats, closeCB, err := reader.LoadAllColumns(reqCtx, idxs, ses.GetMemPool())
if err != nil {
return err
}
defer func() {
if closeCB != nil {
closeCB()
}
}()
bat := bats[0]
p := bat.Vecs[0].GetStringAt(0)
pn := &plan.Plan{}
if err = pn.Unmarshal([]byte(p)); err != nil {
return err
}
a := bat.Vecs[1].GetStringAt(0)
var ast tree.Statement
if ast, err = simpleAstUnmarshal([]byte(a)); err != nil {
return err
}
if err = authenticateCanExecuteStatementAndPlan(reqCtx, ses, ast, pn); err != nil {
return err
}
}
return nil
}
func maySaveQueryResult(ctx context.Context, ses *Session, bat *batch.Batch) error {
if openSaveQueryResult(ctx, ses) {
if err := saveQueryResult(ctx, ses, bat); err != nil {
return err
}
if err := saveQueryResultMeta(ctx, ses); err != nil {
return err
}
}
return nil
}
type simpleAst struct {
Typ int `json:"age"`
// opt which fun of determinePrivilegeSetOfStatement need
}
type astType int
const (
astShowNone astType = iota
astSelect
astShowAboutTable
astExplain
astValues
astExecute
)
func simpleAstMarshal(stmt tree.Statement) ([]byte, error) {
s := simpleAst{}
switch stmt.(type) {
case *tree.Select:
s.Typ = int(astSelect)
case *tree.ShowTables, *tree.ShowSequences, *tree.ShowCreateTable, *tree.ShowColumns, *tree.ShowCreateView, *tree.ShowCreateDatabase:
s.Typ = int(astShowAboutTable)
case *tree.ShowProcessList, *tree.ShowErrors, *tree.ShowWarnings, *tree.ShowVariables,
*tree.ShowStatus, *tree.ShowTarget, *tree.ShowTableStatus,
*tree.ShowGrants, *tree.ShowIndex,
*tree.ShowTableNumber, *tree.ShowColumnNumber,
*tree.ShowTableValues, *tree.ShowNodeList,
*tree.ShowLocks, *tree.ShowFunctionOrProcedureStatus, *tree.ShowConnectors:
s.Typ = int(astShowNone)
case *tree.ExplainFor, *tree.ExplainAnalyze, *tree.ExplainStmt:
s.Typ = int(astExplain)
case *tree.Execute:
s.Typ = int(astExecute)
case *tree.ValuesStatement:
s.Typ = int(astValues)
default:
s.Typ = int(astShowNone)
}
return json.Marshal(s)
}
func simpleAstUnmarshal(b []byte) (tree.Statement, error) {
s := &simpleAst{}
if err := json.Unmarshal(b, s); err != nil {
return nil, err
}
var stmt tree.Statement
switch astType(s.Typ) {
case astSelect:
stmt = &tree.Select{}
case astShowAboutTable:
stmt = &tree.ShowTables{}
case astShowNone:
stmt = &tree.ShowStatus{}
case astExplain:
stmt = &tree.ExplainFor{}
case astExecute:
stmt = &tree.Execute{}
case astValues:
stmt = &tree.ValuesStatement{}
}
return stmt, nil
}
func getTablesFromPlan(p *plan.Plan) string {
if p == nil {
return ""
}
buf := new(strings.Builder)
cnt := 0
if q, ok := p.Plan.(*plan.Plan_Query); ok {
for _, n := range q.Query.Nodes {
if n.NodeType == plan.Node_EXTERNAL_SCAN || n.NodeType == plan.Node_TABLE_SCAN {
if cnt > 0 {
buf.WriteString(", ")
}
buf.WriteString(n.TableDef.Name)
cnt++
}
}
}
return buf.String()
}
func buildQueryResultMetaBatch(m *catalog.Meta, mp *mpool.MPool) (*batch.Batch, error) {
var err error
bat := batch.NewWithSize(len(catalog.MetaColTypes))
bat.SetAttributes(catalog.MetaColNames)
for i, t := range catalog.MetaColTypes {
bat.Vecs[i] = vector.NewVec(t)
}
if err = vector.AppendFixed(bat.Vecs[catalog.QUERY_ID_IDX], types.Uuid(m.QueryId), false, mp); err != nil {
return nil, err
}
if err = vector.AppendBytes(bat.Vecs[catalog.STATEMENT_IDX], []byte(m.Statement), false, mp); err != nil {
return nil, err
}
if err = vector.AppendFixed(bat.Vecs[catalog.ACCOUNT_ID_IDX], m.AccountId, false, mp); err != nil {
return nil, err
}
if err = vector.AppendFixed(bat.Vecs[catalog.ROLE_ID_IDX], m.RoleId, false, mp); err != nil {
return nil, err
}
if err = vector.AppendBytes(bat.Vecs[catalog.RESULT_PATH_IDX], []byte(m.ResultPath), false, mp); err != nil {
return nil, err
}
if err = vector.AppendFixed(bat.Vecs[catalog.CREATE_TIME_IDX], m.CreateTime, false, mp); err != nil {
return nil, err
}
if err = vector.AppendFixed(bat.Vecs[catalog.RESULT_SIZE_IDX], m.ResultSize, false, mp); err != nil {
return nil, err
}
if err = vector.AppendBytes(bat.Vecs[catalog.COLUMNS_IDX], []byte(m.Columns), false, mp); err != nil {
return nil, err
}
if err = vector.AppendBytes(bat.Vecs[catalog.TABLES_IDX], []byte(m.Tables), false, mp); err != nil {
return nil, err
}
if err = vector.AppendFixed(bat.Vecs[catalog.USER_ID_IDX], m.UserId, false, mp); err != nil {
return nil, err
}
if err = vector.AppendFixed(bat.Vecs[catalog.EXPIRED_TIME_IDX], m.ExpiredTime, false, mp); err != nil {
return nil, err
}
if err = vector.AppendBytes(bat.Vecs[catalog.PLAN_IDX], []byte(m.Plan), false, mp); err != nil {
return nil, err
}
if err = vector.AppendBytes(bat.Vecs[catalog.AST_IDX], []byte(m.Ast), false, mp); err != nil {
return nil, err
}
if err = vector.AppendBytes(bat.Vecs[catalog.COLUMN_MAP_IDX], []byte(m.ColumnMap), false, mp); err != nil {
return nil, err
}
return bat, nil
}
// resultFileInfo holds the info of the result file
type resultFileInfo struct {
// the name of the result file
name string
// the size of the result file
size int64
// the block id of the result file
blockIndex int64
}
// doDumpQueryResult reads data from the query result, converts it into csv and saves it into
// the file designated by the path.
func doDumpQueryResult(ctx context.Context, ses *Session, eParam *tree.ExportParam) error {
var err error
var columnDefs *plan.ResultColDef
var reader *blockio.BlockReader
var blocks []objectio.BlockObject
var files []resultFileInfo
//step1: open file handler
if columnDefs, err = openResultMeta(ctx, ses, eParam.QueryId); err != nil {
return err
}
if files, err = getResultFiles(ctx, ses, eParam.QueryId); err != nil {
return err
}
//step2: read every batch from the query result
columnCount := len(columnDefs.ResultCols)
indexes := make([]uint16, columnCount)
for i := range indexes {
indexes[i] = uint16(i)
}
//=====================
// preparation
//=====================
//prepare batch
tmpBatch := batch.NewWithSize(columnCount)
defer tmpBatch.Clean(ses.GetMemPool())
//prepare result set
mrs := &MysqlResultSet{}
typs := make([]types.Type, columnCount)
for i, c := range columnDefs.ResultCols {
typs[i] = types.New(types.T(c.Typ.Id), c.Typ.Width, c.Typ.Scale)
mcol := &MysqlColumn{}
mcol.SetName(c.GetName())
err = convertEngineTypeToMysqlType(ctx, typs[i].Oid, mcol)
if err != nil {
return err
}
mrs.AddColumn(mcol)
}
mrs.Data = make([][]interface{}, 1)
for i := 0; i < 1; i++ {
mrs.Data[i] = make([]interface{}, columnCount)
}
exportParam := &ExportConfig{
userConfig: eParam,
}
//prepare output queue
oq := NewOutputQueue(ctx, ses, columnCount, mrs, exportParam)
oq.reset()
oq.ep.OutTofile = true
//prepare export param
exportParam.DefaultBufSize = getGlobalPu().SV.ExportDataDefaultFlushSize
exportParam.UseFileService = true
exportParam.FileService = getGlobalPu().FileService
exportParam.Ctx = ctx
defer func() {
exportParam.LineBuffer = nil
exportParam.OutputStr = nil
if exportParam.AsyncReader != nil {
_ = exportParam.AsyncReader.Close()
}
if exportParam.AsyncWriter != nil {
_ = exportParam.AsyncWriter.Close()
}
}()
initExportFileParam(exportParam, mrs)
//open output file
if err = openNewFile(ctx, exportParam, mrs); err != nil {
return err
}
//read all files
for _, file := range files {
reader, blocks, err = openResultFile(ctx, ses, file.name, file.size)
if err != nil {
return err
}
quit := false
//read every block
for _, block := range blocks {
select {
case <-ctx.Done():
quit = true
default:
}
if quit {
break
}
tmpBatch.Clean(ses.GetMemPool())
bat, release, err := reader.LoadColumns(ctx, indexes, nil, block.BlockHeader().BlockID().Sequence(), ses.GetMemPool())
if err != nil {
return err
}
defer release()
tmpBatch = bat
//step2.1: converts it into the csv string
//step2.2: writes the csv string into the outfile
n := tmpBatch.RowCount()
for j := 0; j < n; j++ { //row index
select {
case <-ctx.Done():
quit = true
default:
}
if quit {
break
}
_, err = extractRowFromEveryVector(ctx, ses, tmpBatch, j, oq, true)
if err != nil {
return err
}
}
}
}
err = oq.flush()
if err != nil {
return err
}
err = Close(exportParam)
if err != nil {
return err
}
return err
}
// openResultMeta checks the query result of the queryId exists or not
func openResultMeta(ctx context.Context, ses *Session, queryId string) (*plan.ResultColDef, error) {
account := ses.GetTenantInfo()
if account == nil {
return nil, moerr.NewInternalError(ctx, "modump does not work without the account info")
}
metaFile := catalog.BuildQueryResultMetaPath(account.GetTenant(), queryId)
// read meta's meta
reader, err := blockio.NewFileReader(getGlobalPu().FileService, metaFile)
if err != nil {
return nil, err
}
idxs := make([]uint16, 1)
idxs[0] = catalog.COLUMNS_IDX
// read meta's data
bats, closeCB, err := reader.LoadAllColumns(ctx, idxs, ses.GetMemPool())
if err != nil {
if moerr.IsMoErrCode(err, moerr.ErrFileNotFound) {
return nil, moerr.NewResultFileNotFound(ctx, makeResultMetaPath(account.GetTenant(), queryId))
}
return nil, err
}
defer func() {
if closeCB != nil {
closeCB()
}
}()
vec := bats[0].Vecs[0]
def := vec.GetStringAt(0)
r := &plan.ResultColDef{}
if err = r.Unmarshal([]byte(def)); err != nil {
return nil, err
}
return r, err
}
// getResultFiles lists all result files of queryId
func getResultFiles(ctx context.Context, ses *Session, queryId string) ([]resultFileInfo, error) {
_, str, err := ses.GetTxnCompileCtx().GetQueryResultMeta(queryId)
if err != nil {
return nil, err
}
fileList := strings.Split(str, ",")
for i := range fileList {
fileList[i] = strings.TrimSpace(fileList[i])
}
rti := make([]resultFileInfo, 0, len(fileList))
for i, file := range fileList {
e, err := getGlobalPu().FileService.StatFile(ctx, file)
if err != nil {
if moerr.IsMoErrCode(err, moerr.ErrFileNotFound) {
return nil, moerr.NewResultFileNotFound(ctx, file)
}
return nil, err
}
rti = append(rti, resultFileInfo{
name: e.Name,
size: e.Size,
blockIndex: int64(i + 1),
})
}
return rti, nil
}
// openResultFile reads all blocks of the result file
func openResultFile(ctx context.Context, ses *Session, fileName string, fileSize int64) (*blockio.BlockReader, []objectio.BlockObject, error) {
// read result's blocks
filePath := getPathOfQueryResultFile(fileName)
reader, err := blockio.NewFileReader(getGlobalPu().FileService, filePath)
if err != nil {
return nil, nil, err
}
bs, err := reader.LoadAllBlocks(ctx, ses.GetMemPool())
if err != nil {
return nil, nil, err
}
return reader, bs, err
}
// getFileSize finds the fileName in the file handlers ,returns the file size
// and returns -1 if not exists
func getFileSize(files []fileservice.DirEntry, fileName string) int64 {
for _, file := range files {
if file.Name == fileName {
return file.Size
}
}
return -1
}