apstndb

dangling quantified path primary

https://cloud.google.com/spanner/docs/reference/standard-sql/graph-patterns#quantified_paths

quantified_path_primary is not referenced by other rules.

DDL reference should mention about FQN(2024-12-26)

GoogleSQL data definition language https://cloud.google.com/spanner/docs/reference/standard-sql/data-definition-language

Run memefish test cases in spansql.

https://github.com/cloudspannerecosystem/memefish/tree/main/testdata/input

SELECT SUBSTR(TO_HEX(x), 0, 8), SUBSTR(TO_HEX(x), 0, 16)
FROM(SELECT SHA256(CAST(FirstName AS BYTES)) @{DISABLE_INLINE=FALSE} AS x FROM Singers LIMIT 1)

SELECT SUBSTR(TO_HEX(x), 0, 8), SUBSTR(TO_HEX(x), 0, 16)
FROM(SELECT SHA256(CAST(FirstName AS BYTES)) @{DISABLE_INLINE=TRUE} AS x FROM Singers LIMIT 1)

https://issuetracker.google.com/issues/35905569#comment111

DECLARE v1 INT64 DEFAULT 123;
DECLARE v2 INT64 DEFAULT 123;
BEGIN
    SET v1 = @v1;
    SET v2 = @v2;
EXCEPTION WHEN ERROR THEN
 -- nop

$ export PROJECT_ID=gcpug-public-spanner INSTANCE_ID=merpay-sponsored-instance DATABASE_ID=apstndb-sampledb-with-data-idx
$ sh show-schema-tree.sh
Concerts
Singers
  Albums
    Songs
    SongsBySingerAlbumSongNameDesc on Songs
SongGenres
AlbumsByAlbumTitle on Albums

$ gcloud spanner databases execute-sql --project=${PROJECT_ID} --instance=${INSTANCE_ID} ${DATABASE_ID} \
     --sql "$(cat input.sql)" --query-mode=PLAN --format=json | jq -r -f plan.jq
 *0 Distributed Union
 *1   Distributed Cross Apply
  2     Create Batch
  3       Local Distributed Union
  4         Compute Struct
 *5           FilterScan
  6             Index Scan (Index: SongsBySongName)

Unofficial Cloud Spanner operator collection

Query execution operators にはドキュメンテーションされていない operator もあり、 metadata やそれぞれの child links についてもほぼ解説されていないためここにまとめる。

対象: 実行計画を可視化や解析のために処理するツール作成者や、含まれる情報全てをクエリの理解に役立てたいと考えるユーザ

TODO: Metadata や ChildLinks の表の形式化を進める。

実行計画の構造

$ ./go2go run main.go2
true

$ ./go2go translate main.go2
$ cat main.go
// Code generated by go2go; DO NOT EDIT.

	package main

	import (
	"context"
	"encoding/csv"
	"flag"
	"fmt"
	parser "github.com/cloudspannerecosystem/memefish"
	"github.com/cloudspannerecosystem/memefish/token"
	"log"

	import "list"

	a: [{id: 1}, {id: 2}]
	b: [{id: 1}, {id: 1}]
	c: [{id: 1}, {id: 2}, {id: 2}]

	a_ids:: [x.id for x in a]
	a_unique: list.UniqueItems(a_ids)

	unique :: {