duckcros.blogg.se

1. UPDATE OR INSERT INTO CONSTRAINT UPDATE MYSQL TYPESCRIPT HOW TO
2. UPDATE OR INSERT INTO CONSTRAINT UPDATE MYSQL TYPESCRIPT CODE
3. UPDATE OR INSERT INTO CONSTRAINT UPDATE MYSQL TYPESCRIPT FREE
4. UPDATE OR INSERT INTO CONSTRAINT UPDATE MYSQL TYPESCRIPT WINDOWS

UPDATE OR INSERT INTO CONSTRAINT UPDATE MYSQL TYPESCRIPT CODE

Code language: SQL (Structured Query Language) ( sql ) The syntax of INSERT ON DUPLICATE KEY UPDATE statement is as follows: INSERT INTO table (column_list) However, if you specify the ON DUPLICATE KEY UPDATE option in the INSERT statement, MySQL will update the existing row with the new values instead. When you insert a new row into a table if the row causes a duplicate in UNIQUE index or PRIMARY KEY, MySQL will issue an error. The INSERT ON DUPLICATE KEY UPDATE is a MySQL’s extension to the SQL standard’s INSERT statement. Introduction to the MySQL INSERT ON DUPLICATE KEY UPDATE statement

UPDATE OR INSERT INTO CONSTRAINT UPDATE MYSQL TYPESCRIPT HOW TO

LEFT JOIN #table1 on #table1.id = #table2.Summary: in this tutorial, you will learn how to use MySQL INSERT ON DUPLICATE KEY UPDATE statement to update data if a duplicate in the UNIQUE index or PRIMARY KEY error occurs when you insert a row into a table. Print CAST(DATEDIFF(ms, as varchar) + ' milliseconds for insert except'

INSERT INTO ('Insert Except', CAST(DATEDIFF(ms, as varchar)) SELECT id, guidd, TimeAdded, ExtraData from #table1 SELECT id, guidd, TimeAdded, ExtraData from #table2 INSERT INTO #table1 (id, guidd, TimeAdded, ExtraData) Print CAST(DATEDIFF(ms, as varchar) + ' milliseconds for merge' INSERT INTO ('Merge', CAST(DATEDIFF(ms, as varchar)) USING (select Id, guidd, TimeAdded, ExtraData from #table2) as Print CAST(DATEDIFF(ms, as varchar) + ' milliseconds for insert where not exists' INSERT INTO VALUES ('Insert Where Not Exists', CAST(DATEDIFF(ms, as varchar)) WHERE NOT EXISTS (Select Id, guidd from #table1 WHERE #table1.id = #table2.id) Print 'Finished populating the temp tables: ' + CAST(GETDATE() as varchar) INSERT INTO #table1 (Id, guidd, TimeAdded, ExtraData) VALUES table gets every other record so we know there are some to be inserted INSERT INTO #table2 (Id, guidd, TimeAdded, ExtraData) this table gets every record so we know we'll insert some Print 'Populating the temp tables: ' + CAST(GETDATE() as varchar) )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE= OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, FILLFACTOR = 93) ON ) WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON, FILLFACTOR = 93) ON

, uniqueidentifier null -just to have extra dataĬONSTRAINT PRIMARY KEY CLUSTERED Print '# Started at: ' +Cast(GETDATE() as varchar) Leave a comment and share the knowledge if you have any suggestions or other ways of doing this!

UPDATE OR INSERT INTO CONSTRAINT UPDATE MYSQL TYPESCRIPT FREE

The SQL code is below, so feel free to use it as a basis for conducting your own performance benchmarks. Note that results may vary by server because the optimization engine on every SQL Server Instance could do it differently. While it seems to dominate for less than 50,000,000, once that threshold is hit the INSERT EXCEPT option proved to be king. I never thought the LEFT JOIN would slow down as much as it did when hitting 50,000,000 records and more. Who else thought the LEFT JOIN would be the dominant player up through 500,000,000 records and beyond? Time to execute, in milliseconds, over 3 runs: Here are the results, in milli-seconds, as to how long each technique took to execute. To ensure SQL Server didn’t keep any queries (or anything for that matter) cached, the following code was run before each test:

UPDATE OR INSERT INTO CONSTRAINT UPDATE MYSQL TYPESCRIPT WINDOWS

Other than the LEFT JOIN, what are other ways to accomplish this? Here are a few common ways that will be benchmarked:įor testing purposes, the SQL code was executed on a Windows 2012 Server with 128GB memory, 16 core CPU, using Microsoft SQL Server 2014. That’s when this Curious Consultant started wondering what’s the fastest way to insert new records where one doesn’t already exist during a single process? Even though this is simple, is it the fastest way? The age-old technique and I suspect most common practice is doing a left join where the values are null from the table being inserted into. SQL Developers come across this scenario quite often – having to insert records into a table where a record doesn’t already exist. Fastest way to insert new records where one doesn’t already exist