Oracle's CONNECT BY syntax, despite being set-based, offers some limited set-based capabilities: you can use ORDER SIBLINGS BY clause to define the order in which the siblings are returned. However, this would require some additional work to efficiently return only the first branch. In a true...
Forstorage engines that maintain an exact row count per table (such as MyISAM, butnot InnoDB), this Extra value can occur for COUNT(*) queries for which the WHERE clause is missing or always true and there isno GROUP BY clause. (This is an instance of an implicitlygrouped query where ...
Don't say, for example, 'Let me explain you about Jackie'. You can use explain with a that-clause to say that someone tells someone else the reason for something. I explained that I was trying to write a book. Collins COBUILD English Usage © HarperCollins Publishers 1992, 2004, 2011...
filtered- The amount of rows unfiltered by the conditions in the WHERE clause. These rows will be joined to the table in the next row of the EXPLAIN plan. As mentioned previously, this is a guesstimate as well, so MySQL can be wrong with this estimation. ...
As such, Promethean has entered into standard EU model contract clauses with its intragroup companies with which it shares Personal Information to ensure that the transfer of personal data of EU citizens outside the European Economic Area is safeguarded in the same way the data is required to ...
static void show_tablesample(TableSampleClause *tsc, PlanState *planstate, List *ancestors, ExplainState *es);static void show_sort_info(SortState *sortstate, ExplainState *es);static void show_hash_info(HashState *hashstate, ExplainState *es);static void show_tidbitmap_info(BitmapHeapScan...
TheGROUP BYnames only columns that form a leftmost prefix of the index and no other columns. (If, instead ofGROUP BY, the query has aDISTINCTclause, all distinct attributes refer to columns that form a leftmost prefix of the index.) For example, if a tablet1has an index on(c1,c2,c3...
<unionM,N>: The row refers to the union of the rows with id values of M and N. <derivedN>: The row refers to the derived table result for the row with an id value of N. A derived table may result, for example, from a subquery in the FROM clause. <subqueryN>: The row ...
JOIN, COUNT DISTINCT (a JOIN method), and GROUP BY clauses: If no distribution key is configured for the table or the distribution key setting is invalid, data is shuffled among multiple shards during the query. If redistribution occurs when you join multiple tables, the local join feature ...
In previous versions of MongoDB,cursor.explain()returned theclausesarray that detailed the indexes. $sortand$groupStages Whenexplainis run in eitherexecutionStatsorallPlansExecutionverbosity mode, the$sortand$groupstages have additional output.