In the database structured query language (SQL), the DELETE statement removes one or more records from a table.

learn more… | top users | synonyms

0
votes
1answer
688 views

Delete Query takes a long time

I have a innodb table that counts circa 1 billion entries. I started a delete operation (with a small where condition on an indexed column) that should delete a lot entries, leaving circa 100 million. ...
2
votes
2answers
389 views

How do I Delete A Database And Log Files With SQL 2008 Script?

While working on making an automated Delete and Restore script for my backups I ran into a snag. I can not delete the database; however, the delete button works exactly how I need it to. Can anyone ...
0
votes
1answer
429 views

Effective duplication of DELETE … LIMIT in Pg

I have an unusual problem: I need to delete a certain number records from a table, of a particular type; in certain non-compliant DBs it would be easy to accomplish this with DELETE FROM sometable ...
0
votes
1answer
330 views

Delete millions of rows, fast

I currently have a database with the following structure: id->varchar(9) time->datetime val01 - val20->int(11) val21 - val40->tinyint(1) id and time are the primary key. also I defined an index ...
4
votes
1answer
579 views

Deleting Rows is Increasing Index Size

We have a very large table in a SQL Server 2008 R2 Standard server which I am archiving rows by copying them into another database on a separate disk and then deleting them from the original table ...
2
votes
4answers
512 views

MySQL: Keep the 10 most recent rows for each user

I have a table saving scores for a game that have 3 columns (more in practice, but it is easier for everyone this way): userid : the id of the user that got the score timestamp: the time the score ...
2
votes
1answer
57 views

Single statement or batched delete?

I need to delete 6.3 million records from 25 tables in production. I have the following two queries, but I don't know which one will be best: delete jc from Jtable jc join J1Table j on j.JobId = ...
0
votes
1answer
131 views

Multiple source CASCADE DELETE behavior

I'm having trouble understanding Postgres's CASCADE DELETE behavior. If table_A REFERENCES table_B, and the column referenced could have multiple instances of the same value, will the table_A row be ...
0
votes
1answer
249 views

I have delete database from mysql but storage is not freed

I have deleted multiple databases (schema) from mysql on amazon RDS but the storage is not freed, is there anything else I should do to free up the storage? I have a mysql database that the total ...
3
votes
1answer
528 views

Is it possible to raiserror within a For Delete Trigger that rolls back the deletes

There is a claim at the end of this accepted answer that if an error occurs within a "For Delete" trigger, the delete action would be rolled back because it is part of an implicit transaction. ...
2
votes
0answers
218 views

Postgres 9.3 - deletes terribly slow for 10 minutes after dropping indexes/constraints

If I run a script which drops indexes (17 of them, CONCURRENTLY makes no difference except that without it I get the occasional deadlock), then constraints (20 constraints on 18 tables) and then run a ...
5
votes
1answer
644 views

Use of FROM keyword on DELETE statement

The BOL and many other sources point out: FROM Is an optional keyword that can be used between the DELETE keyword and the target table_or_view_name, or rowset_function_limited. I'm used to ...
3
votes
1answer
2k views

Why is SQL Server using a clustered index scan for a self referencing FK cascade delete

I have made an example to allow me to show what my issue is: Setup: CREATE TABLE [dbo].[Test]( [TestId] [bigint] IDENTITY(1,1) NOT NULL, [ParentTestId] [bigint] NULL, CONSTRAINT [PK_Test] ...
1
vote
3answers
95 views

SQL Delete rows where a dataname will equal mulitple variables

Researching similar common queries have really helped but I am still none the wiser as to my issue. To note that the database I intend to use this on contains around 1000 rows (same 2 columns listed ...
1
vote
2answers
11k views

Delete an oracle instance, the right way

I want to delete an oracle instance (oracle 10.2.0.4.0) created in the AIX 6.0 OS. I know i can delete all the dbf and ctl files in the Terminal but i thinks that's no the best way to do it. I think ...
0
votes
2answers
1k views

Massive MySQL delete from CSV file

To insert massive CSV file into MySQL, there is LOAD DATA INFILE, but is there any similar command to delete massive entries with keys stored in a massive CSV file? If not, what would you see as the ...
0
votes
1answer
840 views

Deleting Record from Linked Table Slow in MS Access

I have a Microsoft Access database that is linked to a SQL Server 2000 backend. It has one form with several subforms, all using information from linked tables. When I try to delete a record from one ...
0
votes
2answers
562 views

Trigger to delete inserted record if it doesn't exist in another table

I have a question. I have two tables: zip_code (zip_id, zip_code, state) - this is a static table that stores areas I service tech_zips (tz_id, tech_id, zip) - this is where I store what zip codes ...
3
votes
2answers
293 views

Is it good practice to check for existence of records before deleting them

I've came across the following SQL/PLSQL while investigating a stored procedure written by someone else: 1. V_COUNT NUMBER(5,0); ......... 2. SELECT COUNT(*) INTO V_COUNT FROM TABLE1 WHERE ...
2
votes
1answer
300 views

Deleting 200M+ rows from InnoDB table

Basically, we have a table with the following structure: CREATE TABLE `reqs` ( `id` INT(10) NOT NULL AUTO_INCREMENT, `reqid` BIGINT(20) NOT NULL, `from` BIGINT(20) NOT NULL, `to` ...
0
votes
2answers
2k views

Delete rows in parent table based on criteria in child table - Oracle

I have a table B with a foreign key to table A. I want to DELETE some rows in table B, and I also want to DELETE their parent rows in table A. However, the delete criteria is based on table B. The ...
4
votes
3answers
2k views

Is there any time where we should avoid cascading delete?

In SQL Server 2008, there is a Primary table which is linked to three other child tables by 1 to many relationship. So, we are thinking of using Cascading delete in the primary table, so that all the ...
1
vote
1answer
900 views

How to avoid locks by large transactions?

We have a large application running, that requires cleanup for performance reasons. This was however not forseen when designing the application. Basically, the delete is executed from a stored ...
0
votes
1answer
272 views

DELETE query against a linked server issues error

I have a query that is part of a bigger process, and runs against a linked server. The code is like this: DELETE FROM [LinkServerIP].[Database].[dbo].[TableName] WHERE NOT EXISTS ( SELECT * ...
1
vote
1answer
757 views

MySQL: update instead of delete if foreign key constraint?

I have a bit of a strange question. I know about insert on duplicate key update. My question is, is there something similar for deletes that fail because of foreign key constraints? For example: ...
1
vote
2answers
2k views

Freeing space after deleting rows [duplicate]

I have a SQL Server 2008 instance and one table is quite large (log data) so I delete old logs. Now I start to read articles on this problem, here is one. As I see it there is no solution! If I ...
6
votes
2answers
535 views

What to do after deleting a million records

We are implementing a new feature in our system that will cause about a million records (each record is tiny, basically a GUID, a date, and four smallint fields) to be purged from a table every night. ...
0
votes
1answer
362 views

Mysql foreign key cascade delete

Does mysql have a way to delete all sub links if a row was deleted from a "parent" table? Example table setup is below, the issue I am trying to avoid is having to maintain a script that deletes the ...
0
votes
0answers
133 views

Importing large .sql file stops before even midway and starts deleting

Okay so i'm trying to import my minecraft servers .sql file into database and after first 1GB of importing data it stops without error and starts deleting what already has been imported any ideas? ...
1
vote
1answer
1k views

mysqldump: replace drop table in output with delete?

I am using mysqldump to dump some records in a table: mysqldump mydatabase mytable --where="field=value" this emits script that includes drop table mytable statement. Since I use the --where ...
0
votes
3answers
577 views

MySQL Large DELETE with JOINs

I have a large table players with ~20MM rows which joins to a table stats with ~300MM rows, among others (photos, ...). I want to DELETE all records for players that were born_on before 1950. I ...
1
vote
1answer
553 views

Large table delete in mysql

I want to delete a table with 10,000,000 records. Due to some restrictions I can't do truncate on that table (I don't have the DROP privilege), I can think of two options: DELETE QUICK To set some ...
2
votes
1answer
3k views

MySQL Query: Delete from 'table2' where column = 'value' IF column in 'table1' = 'value'

I am trying to execute a MySQL query to delete rows from 'table2' where column = 'value' IF column in 'table1' = 'value' I have 2 tables... Table 1 is called accounts Table 2 is called ...
-3
votes
1answer
126 views

What will the sql statement “DELETE FROM sales” do?

DELETE FROM sales; And if there are no other uncommitted transactions on the sales table. Which statement is true about the DELETE statement? It removes all the rows in the table and deleted rows ...
4
votes
5answers
2k views

Fast way of delete MySQL record

I have a 1.2 million record in a database table( it use index column also) I want to delete old 1 million record. I try to do it using PhpMyadmin but it take more time. DELETE FROM `table` WHERE ...
0
votes
1answer
6k views

Delete from table where multiple fields match select subquery from other table

I want to delete an entry in a table where multiple fields match the results of another select subquery which takes data from another table. This is what I have so far, though it doesn't work: ...
1
vote
2answers
608 views

Approaches for deleting unnecessary records from tables

We have a database which stores the temperatures of 20 thermometer every 7 seconds. We want to delete all records in the way that every minute holds just one tempereature instead of 8 which are older ...
0
votes
1answer
211 views

Need ideas about OPTIMIZE TABLE

Looking at a database with 10 tables and fairly active at by-the-hour changes. On the first of each month, I purge some rows from 3 tables to remove outdated material and keep the size down. All of ...
1
vote
1answer
481 views

Delete entry from related tables

I can not use InnoDB engine because of some dependency troubles in LuaSQL and PtokaX. My current query is something like: DELETE e.*, m.* FROM entries e INNER JOIN magnets m ON m.eid = ...
2
votes
4answers
611 views

Delete the N oldest entries grouped by multiple columns

I´d like to delete the oldest entries of my database, but in each category shall remain at least N words of each char. Structure of TABLE words id | word | char | category For example I have the ...
2
votes
1answer
418 views

Will deleting data in master automatically delete data in slave?

I have data replication setup on MySQL. If I delete data on the master, will replication know data was deleted and automatically delete the same data on slave?
1
vote
2answers
2k views

Fastest way to delete matching rows in MySQL?

I have more than 10 million records in a table. I want to delete the records where the email column contains .ac.. What is the fastest method to perform the task? Table Schema CREATE TABLE `master` ...
3
votes
1answer
5k views

Very slow DELETE in PostgreSQL, workaround?

I have a database on PostgreSQL 9.2 that has a main schema with around 70 tables and a variable number of identically structured per-client schemas of 30 tables each. The client schemas have foreign ...
5
votes
2answers
3k views

Why is truncate DDL?

I have an interview question, which being asked during my interview. I answered the question, but interviewer was not convinced with my answer. So, please let me know the what would be the correct ...
2
votes
1answer
90 views

What is the equivalent of a “Certificate of Destruction” when using a cloud-hosted database?

We have a Rails application hosted by Heroku and using an Heroku Postgres database. Some of the information we store is considered to be sensitive by our users, and we've been asked if we can provide ...
1
vote
1answer
500 views

mysql query - how to delete duplicates based on highest int?

I'm running a reverse auction website and I need to delete the duplicate bids and keep only the highest amount . lastPriceBid_rounded is the "amount". The duplicate is defined by the userId. ...
1
vote
1answer
159 views

Mysql setting a record as deleted or archive

Is there any way to omit some records in mysql select statement and not deleting them? We can easily add a column for example deleted and set it to 1 for deleted ones and keep them but the problem is ...
3
votes
1answer
4k views

Most efficient way of bulk deleting rows from postgres

I'm wondering what the most efficient way would be to delete large numbers of rows from PostgreSQL, this process would be part of a recurring task every day to bulk import data (a delta of insertions ...
2
votes
2answers
317 views

Inserting data to a table which is being cleaned up by SQL job at the same time

Our app uses a table in a database and we have a Sql job set up to run overnight which executes a stored procedure which just deletes data older that from the table. DELETE FROM MyTable ...
1
vote
1answer
265 views

Delete word, its meanings, its meaning's example sentences from DB

I have three tables as below (simplified for demonstration): words ===== integer id text word meanings ======== integer id integer word_id text meaning examples ======== integer id integer ...