I want to select about 5,000 of those rows at random.我想随机选择大约5,000行。I've thought of a complicated way, creating a temp table with a "random number" column, copying my table into that, looping through the temp
SELECT TOP 1 column FROM table ORDER BY NEWID() Select a random row with IBM DB2: SELECT column, RAND() as IDX FROM table ORDER BY IDX FETCH FIRST 1 ROWS ONLY Select a random record with Oracle: SELECT column FROM ( SELECT column FROM table ORDER BY bms_random.value ) WHERE rownum ...
SELECT TOP 1 column FROM tableORDER BYNEWID() Select a random row with IBM DB2 SELECT column, RAND() as IDX FROM table ORDER BY IDX FETCH FIRST 1 ROWS ONLY ThanksTim Select a random record with Oracle: SELECT column FROM( SELECT column FROM tableORDER BY dbms_random.value )WHERE rownum...
SELECT DISTINCT 1 + trunc(random() * 5100000)::integer AS id FROM generate_series(1, 1100) g ) r JOIN big USING (id) LIMIT 1000; 使用rCTE 进行优化 特别是如果您对差距和估计不太确定。 WITH RECURSIVE random_pick AS ( SELECT * FROM ( SELECT 1 + trunc(random() * 5100000)::int AS ...
SELECT column FROM tableORDER BYRANDOM()LIMIT 1 1. Select a random row with Microsoft SQL Server: SELECT TOP 1 column FROM tableORDER BYNEWID() 1. Select a random row with IBM DB2 SELECT column, RAND() as IDX FROM table ORDER BY IDX FETCH FIRST 1 ROWS ONLY ...
SELECT column, RAND() as IDX txt AI代码解释 FROM table txt AI代码解释 ORDER BY IDX FETCH FIRST 1 ROWS ONLY 用Oracle选择一个随机记录: txt AI代码解释 SELECT column FROM txt AI代码解释 ( SELECT column FROM table txt AI代码解释 ORDER BY dbms_random.value ) txt AI代码解释 WHERE rownum ...
//Creates a random integer between 0 and the number of elements within the collection Random rand = new Random(); int toSkip = rand.Next(0, context.Table1.Count); //This will select a single row within the collection and return it return context.Table1.Skip(toSkip).Take(1).First()...
select data_1.tid1,data_1.id from row_num as row_num inner join data_1 as data_1 on data_1.tid1 = row_num.tid2 最后轮到 POSTGRESQL , 但是这样做性能在大数据量上是一个问题。 select d.* from (select floor(random() * (max(id) - min(id))) as id from test_d) as ma ...
If more than 102,400 rows are estimated, a BULK INSERT is initiated. For more information, see KB2998301.Scope: Global or session or query (QUERYTRACEON). 9349 Disables batch mode for top N sort operator. SQL Server 2016 (13.x) introduced a new batch mode top sort operator that boost...
將DBPROP_CANHOLDROWS 和 DBPROP_IRowsetChange 同時設定為 VARIANT_TRUE 意味者加上書籤的資料列集。 如果兩個屬性都為 VARIANT_TRUE,在資料列集上會提供 IRowsetLocate 介面,而且 DBPROP_BOOKMARKS 和 DBPROP_LITERALBOOKMARKS 都為 VARIANT_TRUE。 SQL Server 資料指標支援包含書籤的 OLE DB Driver for SQL...