pentaho insert update performance

disk space, the table becomes fragmented after the delete operation, which results in a significant performance degradation, which occurs after multiple update operations. If you collect statistics but do not see significant performance improvements, it may be helpful to reorganize the table data. When the table data is reorganized, the physical order of the dat

Original: Performance optimization-Statistics--sqlserver Automatic Update and auto-create statistics optionsOriginal translation from: Http://www.mssqltips.com/sqlservertip/2766/sql-server-auto-update-and-auto-create-statistics-options/?utm _source=dailynewsletterutm_medium=emailutm_content=headlineutm_campaign=2012913How does statistical information improve SQL

. According to the execution plan, two articles are scanned for table B/index;If the where condition is discarded, the entire table is created for table A by default.Update, but because (select B. city_name from tmp_cust_city B whereWhere B. customer_id = a. customer_id)It may not provide "enough" value, because tmp_cust_city is only part of the customer's information,Therefore, an error is returned (if the specified column -- city_name can be NULL, it is another question ): 01407,000 00, "canno

= gbk 2. Create Test Data The Code is as follows: Copy code $ Db = mysql_connect ("localhost", "root ","");Mysql_select_db ("test ");Set_time_limit (0 );$ Table = 'test007 ';For ($ I = 0; I I $ K1 = rand (random );$ K2 = rand (0, 3 );$ K3 = rand (1,100000 );Mysql_query ("insert into $ table (key1, key2, key3) values ('". $ k1 ."','". $ k2 ."','". $ k3. "')", $ db );}?> Note: 1000000 (100 million records) records

their data. Remember, select out, processing, one-time insert new table, do not insert! The end result, with a Select + where + order by + Limit method (with primary key to deal with where and order by), about a minute to deal with 5 million or so of data, there are several tables, of which two tables each have 1 million or 2 million pieces of data, The original one-by-one

their data. Remember, select out, processing, one-time insert new table, do not insert! The end result, with a Select + where + order by + Limit method (with primary key to deal with where and order by), about a minute to deal with 5 million or so of data, there are several tables, of which two tables each have 1 million or 2 million pieces of data, The original one-by-one

.SourceColumn = "customerid "; Cmd. Parameters. Insert (0, p1 ); Cmd. Parameters. Insert (0, p2 ); Cmd. UpdatedRowSource = UpdateRowSource. None; Da. UpdateCommand = cmd; Da. UpdateBatchSize = 10; Da. Update (ds, "mycustomers "); Console. WriteLine ("Updating:" + updating ); Console. WriteLine ("Updated:" + updated ); Console. ReadLine (); } Static void da_RowUpd

; end Loop;end; 5) A special case of associated update and its performance re-discussionIn Oracle's UPDATE statement syntax, in addition to the Update table, you can also be a view, so there are 1 exceptions:SQL CodeUpdate (Select as new_name from customers a,tmp_cust_city bwhere b.customer_id=a.customer_id)set city_n

Original translation from: Http://www.mssqltips.com/sqlservertip/2766/sql-server-auto-update-and-auto-create-statistics-options/?utm _source=dailynewsletterutm_medium=emailutm_content=headlineutm_campaign=2012913How does statistical information improve SQL Server query performance? The statistical histogram is used as the basis for selecting the query optimizer in the query execution plan. If a query predic

performance issues with spring's jdbctemplate batch update These two days accidentally found a jdbctemplate batch update performance problem, the problem is such a one-time bulk Delete and insert 3,000 records, incredibly used 400s I was also frightened. I also looked at th