bushy join CBQT Cost Based Query Transformation CBQT_OR_EXPANSION Cost Based OR Expansion CVM...unnest query block VECTOR_AGG Vector Transformation CURSOR_SHARING Cursor sharing DML DML...Partial Join Evaluation PARTITION Partition PQ Parallel Query PARALLEL Parallel table...unnest query block VECTOR_AGG Vector Transformation CLUSTER_BY_ROWID Cluster By Rowid Transformation...SVM Simple View Merging TABLE_ELIM Table Elimination UNNEST unnest query block USE_CONCAT Or-optimization
内置缓存以消除跨查询的冗余模型调用⌨️ 对 PyTorch 和 HuggingFace 模型的一流支持 可通过 pip 安装并完全在 Python 中实现以下是一些说明性的 EVA 支持的应用程序(它们都是可以在 Google...考虑对 图像数据集的这两个探索性查询: -- Query 1: Find all images of black-colored dogs SELECT id, bbox FROM dogs...JOIN LATERAL UNNEST(Yolo(data)) AS Obj(label, bbox, score) WHERE Obj.label = 'dog' AND Color(Crop...(data, bbox)) = 'black'; -- Query 2: Find all Great Danes that are black-colored SELECT id, bbox FROM...dogs JOIN LATERAL UNNEST(Yolo(data)) AS Obj(label, bbox, score) WHERE Obj.label = 'dog' AND
子查询关联集展开机能(unnest correlation set subquery) 这个机能,我在 Google 上查了一下,分享的文章特别少,可能是很少被关注到吧。...SQL> alter session set "_optimizer_unnest_corr_set_subq" = TRUE; SQL> select key from drv where exists...---- | 0 | SELECT STATEMENT | | 1 | 18 | 29 (0)| 00:00:01 | |* 1 | HASH JOIN...Final query after transformations:******* UNPARSED QUERY IS ******* SELECT "DRV"."...上面的例子也可以看出来,这个机能是用隐藏参数 “_optimizer_unnest_corr_set_subq” 来控制的。
.* from t1 where c2 in (select /*+ NO_UNNEST */ c2 from t2); C1 C2 ---------- -------...*/ 0 FROM "T2" "T2" WHERE "C2"=:B1)) 3 - filter("C2"=:B1) 这种情况下,显然没有直接用 JOIN 来 access...作出来的执行计划里,IN 的时候是 SEMI JOIN ,NOT IN 的时候是 ANTI JOIN。...Final query after transformations:******* UNPARSED QUERY IS ******* SELECT "T1"."C1" "C1","T1"."...有以下两种方法: 隐含参数 _UNNEST_SUBQUERY 设置成 false OR 最开始例子里面用到的 NO_UNNEST hint。
我们在用psql登陆时,增加-E选项即可,示例如下: postgres=# \d+ test_table ********* QUERY ********** SELECT c.oid, n.nspname..., c.relname FROM pg_catalog.pg_class c LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace...a.attstorage , pg_catalog.col_description(a.attrelid, a.attnum) FROM pg_catalog.pg_attribute a LEFT OUTER JOIN...********** WITH att_arr AS (SELECT unnest(paratts) FROM pg_catalog.pg_partition p WHERE p.parrelid...33410' AND p.parlevel = 0 AND p.paristemplate = false), idx_att AS (SELECT row_number() OVER() AS idx, unnest
SQL 查询,query.mentions。...query "mentions" { sql = <<EOQ with names as ( select unnest( $1::text[] ) as name...Powerpipe 将名称作为字符串数组传递,这是一个本机 Postgres 类型,可以使用其 unnest 函数展开。...locals { joined_companies = join(",", local.companies) joined_languages = join(",", local.languages...和 unnest 函数,展开非常简单。
从上面可知,标量子查询转换成了 hash join outer,性能分析可知表 tab1 只扫描了一次,整个 SQL 消耗的逻辑读为 555。...OBJECT_TYPE" OJE: Begin: find best directive for query block SEL$841DDE77 (#1) OJE: Considering outer-join...16344),compile(in-use=113288, alloc=115544), execution(in-use=3432, alloc=4032) SJC: Considering set-join...,可以先尝试更改为 false,或者用hint(no_unnest) 避免子查询展开。..."=false 将其关闭此功能,或者用 hint no_unnest 来避免子查询展开。
JE:[V2] Considering Join Elimination on query block SEL$1 (#0) ************************* Join Elimination...OBJECT_ID" JE:[V2] Query block (0x7efe755b98b0) before join elimination: SQL:******* UNPARSED QUERY IS...NTSID JE:[V2]: Cannot eliminate ENMO by ref. join elim - no constr. based join pred(s) JE:[V2] Query...OBJECT_ID" JE:[V2] Query block (0x7efe755b98b0) before join elimination: SQL:******* UNPARSED QUERY IS...NTSID JE:[V2]: Cannot eliminate ENMO by ref. join elim - no constr. based join pred(s) JE:[V2] Query
url_extract_query(url) 提取出URL中的query,结果为varchar类型。...to_big_endian_64(bigint) → varbinary 把数字转化成大端表示的二进制。...from_big_endian_64(binary) → bigint 把大端表示的二进制字符串转化成数字。 md5(binary) → varbinary 计算二进制字符串的md5。...SQL中常用的4个join用法 inner join left (outer) join right (outer) join full outer join 牢记此图!...mysql中目前没有full join功能 unnest语法 背景 在复杂的业务场景下,日志数据的某一列可能会是较为复杂的格式,例如数组(array)、对象(map)、JSON等格式。
一种是用新记录更新现有记录,另一种是插入不存在的全新记录(LEFT JOIN 情况)。 MERGE是关系数据库中常用的语句。...Google BigQuery MERGE 命令是数据操作语言 (DML) 语句之一。它通常用于在一条语句中自动执行三个主要功能。这些函数是 UPDATE、INSERT 和 DELETE。...这意味着 Google BigQuery MERGE 命令可让您通过更新、插入和删除 Google BigQuery 表中的数据来合并 Google BigQuery 数据。...2020-10-10 16:46:59.878 UTC' as event_timestamp, 'join_group' as event_name), ('0003',12,timestamp...from object ) , splits as ( select base_currency, pair, split(pair, ':') positions from data cross join
oracle中的join的整理和结构分析 在Oracle中的join主要分为: 外连接(outter join),内连接(inner join),自身连接(self-join) 外连接(outter join...在sql语句(structured Query Language)是:table_1 left/right/full outer join table_2,通常我们省略outer。...左外连接(left outer join) Sql代码 select * from out_join1 left outer join out_join2 on out_join1.id_1=out_join2...全外连接(full outer join) Sql代码 select * from out_join1 full join out_join2 on out_join1.id_1=out_join2...内连接(inner join) Sql代码 select * from out_join1 inner join out_join2 on out_join1.id_1=out_join2.id_2
e.oid, evtname, evtenabled, evtevent, evtowner, array_to_string(array(select quote_literal(x) from unnest...* Initialize prepared-query state to "nothing prepared"....(query, AH->sync_snapshot_id, conn); ExecuteSqlStatement(AH, query->data); destroyPQExpBuffer(query...(&tblinfo[i])); /* Arbitrarily end a batch when query length reaches 100K. */ if (query->len...ACCESS SHARE MODE"); ExecuteSqlStatement(fout, query->data); resetPQExpBuffer(query)
NO_STAR_TRANSFORMATION Do not use star transformation (from Oracle 10g) UNNEST The UNNEST hint specifies...NO_UNNEST Use of the NO_UNNEST hint turns off unnesting for specific subquery blocks....HASH_SJ Use a Hash Anti-Join to evaluate a NOT IN sub-query....Use this when your high volume NOT IN sub-query is using a FILTER or NESTED LOOPS join....(depricated in Oracle 10g) NL_AJ Use an anti-join in a sub-query.
FilterJoinRule.FILTER_ON_JOIN, // push filter into the children of a join FilterJoinRule.JOIN...PushProjectIntoTableSourceScanRule.INSTANCE, PushFilterIntoTableSourceScanRule.INSTANCE, // Unnest...: values | { select | selectWithoutFrom | query UNION [ ALL ] query | query...EXCEPT query | query INTERSECT query } [ ORDER BY orderItem [, orderItem ]* ] [ LIMIT...schemaName . ] tableName | LATERAL TABLE '(' functionName '(' expression [, expression ]* ')' ')' | UNNEST
Hash Join 在Spark 和 Flink的SQL部分进行Join的时候都会被用到,之前我们发过一篇文章,《SparkSQL的3种Join实现》。...简单的说就是两层循环,用第一张表做Outter Loop,第二张表做Inner Loop,Outter Loop的每一条记录跟Inner Loop的记录作比较,找出符合条件的数据。...再看有索引时的 block nested loop 方法,增加索引: mysql> CREATE index idx1 ON t1(c1); Query OK, 0 rows affected (7.39...sec) Records: 0 Duplicates: 0 Warnings: 0 mysql> CREATE index idx2 ON t2(c1); Query OK, 0 rows affected...(6.77 sec) Records: 0 Duplicates: 0 Warnings: 0 mysql> CREATE index idx3 ON t3(c1); Query OK, 0 rows
>Add(new PartitionedHashJoinPlanNode()); break; case TPlanNodeType::NESTED_LOOP_JOIN_NODE...*node = pool->Add(new SubplanPlanNode()); break; case TPlanNodeType::UNNEST_NODE...if (tnode_->kudu_scan_node.use_mt_scan_node) { DCHECK_GT(state->query_options...this, state->desc_tbl())); } else { DCHECK(state->query_options...().mt_dop == 0 || state->query_options().num_scanner_threads == 1); *node = pool->Add
= t.no and c.name = 'Database System' and t.name = 'Jennifer'; QUERY...ExecProcNode每次调用时: 【1】首先拉动语法树根节点:例如上面例子中,会先执行ExecNestLoop,在执行ExecNestLoop时,该节点因为缺数据无法循环嵌套链接,所以肯定要拉动outter...plan(hash join)和inner plan(index scan)把需要循环嵌套连接的两个数据拿回来,才能执行连接。...【2】然后hash join在执行时,又会拉动seqscan节点去扫描拿到元组。...QUERY PLAN -----------------------------------------------------
[localhost:21000] > explain select count(*) from medium join big where big.id = medium.id; Query: explain...select count(*) from medium join big where big.id = medium.id +-------------------------------------...big where big.id = small.id; Query: explain select count(*) from small join big where big.id = small.id...join small on (big.id = small.id); Query: select count(*) from big join small on (big.id = small.id)...big on (big.id = small.id); Query: select count(*) from small join big on (big.id = small.id) +-----
(SELECT uid, query FROM table_B WHERE dt='$date' AND hour='${hour...}' ) b WHERE instr(b.query, a.word) > 0;一开始怀疑是不是两表进行 shuffle join 导致的性能差,通过 Explain Verbose...查看,发现是 instr(b.query, a.word) 这个非等值条件导致使用 NESTLOOP JOIN。...后再打平,改进后的 SQL 如下:SELECT t.pid, b.uidFROM table_xx aJOIN search_expo bCROSS JOIN UNNEST(SPLIT(...a.pid_list, ',')) AS t(pid)WHERE INSTR(b.query, a.word) > 0;优化后的结果,从原来的十几分钟耗时减少到 3 分钟内;通过执行计划,我们可以分析: