Questions tagged [limits]
The limits tag has no usage guidance.
90
questions
0
votes
1
answer
148
views
Can I set a row-limit for query results that throws an ERROR if the result set exceeds that limit?
I'm looking for a way to protect my database against runaway queries issued by an application. I have control over both the application and the database. It occurs to me that I can protect against two ...
0
votes
1
answer
71
views
'Limit INT OFFSET @variable' throw runtime error in mysql server
I'm trying to solve this problem in Hackerrand
The problem asks for the median in a specific column
my code:
SET @VAE = (SELECT COUNT(*) FROM STATION);
SET @VAE1 = ROUND(@VAE/2)-1;
SELECT LAT_N FROM ...
0
votes
1
answer
353
views
Why does my LIMITed SELECT fetch the last record of the table, not the first?
I read that to fetch the first table record, you may use LIMIT 1. I tried to apply that knowledge to my JOIN statement and got a diametrically opposite result. It joined the last record of the joined ...
0
votes
0
answers
34
views
Tabular Cube SSAS Enterprise - Ignoring "LowMemoryLimit"(And All Others)
I have a really big SSAS Tabular cube server, it's has about 1TB of available memory(x1e.8xlarge). I have allot of cubes on it, it's great, I want to add more, I've added a new one and unfortunately I'...
2
votes
1
answer
37
views
How to get the most recent result sets when grouping key and date are in separate tables
Good evening! I'm having some difficulty. I'm trying to obtain the most recent row from a few tables using SQL. I can do this using a loop in code, but it requires a lot of round trips to the database ...
3
votes
1
answer
364
views
How to limit the amount of values within a postgres table which are updated
using the following sample:
CREATE TABLE tbl(
x integer,
y integer
)
INSERT INTO tbl
SELECT g AS x FROM generate_series(1, 10) AS g;
Which gives:
x | y
----+---
1 |
2 |
3 |
...
0
votes
1
answer
144
views
MariaDB: Limit changes query plan and makes query very slow
It's counter-intuitive and weird to see how adding "LIMIT 2" changes whole plan for MariaDB (version 10.6.7) from using one index and having total time of 2 seconds into another index with ...
0
votes
1
answer
523
views
How to limit CPU by Db2 instance?
On Linux/x86_64 I have several Db2 database instances and most of them have one database per instance.
Today I have had one "run away instance" that consumed most of the CPU resources of ...
0
votes
0
answers
317
views
MySQL query: multiple select with different conditions and LIMIT for each, but also LIMIT whole query + paginator friendly
I would like to write SQL query (for MySQL) that is able to SELECT
x rows by condition1 from table1
y rows by condition2 from table1+join1
z rows by condition3 from table1+join2
But on every page (...
2
votes
3
answers
59
views
How do I block all IP addresses from connecting remotely to Cassandra?
I want access to remote cassandra with one ip address. how can I change cassandra.yaml to block all ip address except ip that I want to connect?
Can I do by cassandra.yaml ?
0
votes
2
answers
3k
views
How to limit the number of rows in a mysql table
How can I set a limit of rows to a mysql table? (I am using php)
POSSIBLE METHOD-1:
When the user tries to SIGN-UP I can select everything from the TABLE and get the number of ROWS in the TABLE and ...
1
vote
0
answers
627
views
Very slow MariaDB query when adding ORDER BY/LIMIT but there are no rows
I am facing an issue with MariaDB 10.1 on a log table with the following (simplified) structure:
CREATE TABLE logs (
log_id INT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
log_date TIMESTAMP DEFAULT ...
0
votes
1
answer
963
views
Best practice for SQL table names when using sub namespaces that exceed maximum table name length
I have a MySQL database that includes many tables named according to a namespace that uses sub names and underscores (_ as in a_b_c), such as the following:
life_domain_kingdom_phylum
...
2
votes
1
answer
2k
views
Limiting the number of records from nested INNER JOIN table
The context is as follows:
We have 3 tables: We'll call them A,B and C.
A has a foreign key referencing table B, we'll call it "bId". The relationship is a ManyToOne. (One record in B can ...
0
votes
1
answer
175
views
mySQL Query with a LIMIT on a row value
I am trying to replace a lot of queries like this with a single query.
SELECT * FROM y WHERE x = a ORDER BY timestamp LIMIT 50
SELECT * FROM y WHERE x = b ORDER by timestamp LIMIT 50
SELECT * FROM y ...
0
votes
1
answer
340
views
data model limit rows per user
This is regarding to postgres that I was asked to create data model which has a relationship with user.
For example a new data model called Comment M:1 User, but while creating the data model is it ...
0
votes
1
answer
167
views
Determine Available Blocks of Contiguous Ids
We have a SQL Server table that has an int autoincrement primary key column on it.
The table's primary key space is fragmented. For example, ids 1 through 10 are in use but then ids 11 through 100,000 ...
0
votes
1
answer
50
views
Fill remaining LIMIT rows selection if conditions met are less than LIMIT number
I have a MySQL database with data in it. They all have locations (London, Liverpool, etc), I want a query to select 10 random rows with a location (for example London), and if there aren't enough to ...
3
votes
1
answer
7k
views
How to use ORDER BY and LIMIT inside JSON_AGG
I have a query which returns a desired output.
SELECT
shop,
JSON_AGG(item_history.* ORDER BY created_date DESC) as data
FROM item_history
GROUP BY
shop;
Results:
[
{
"shop&...
0
votes
1
answer
42
views
MySQL replication username
What is the difference in using these two approaches when setting master-slave replication:
Setting the binlog-do-db option on the master to choose which DBs are going to be replicated;
Creating a ...
0
votes
2
answers
466
views
How to limit tree traversal in case of loops?
So I want to limit tree depth traversal (as the simplest recursion killer tool). Example code that turns normalized records into tree:
CREATE TABLE items (
item_id serial PRIMARY KEY,
title ...
0
votes
0
answers
343
views
postgresql, connection limit for different roles
Is possible setup in postgresql.conf connection limit for specified role globally (in some .conf file) or individually?
For example, I have 3 roles and max_connections = 600.
Need to setup max 10 ...
1
vote
1
answer
690
views
LIMIT and OFFSET a complex query
I have a query generated by a ORM (Sequelize), i ran into an issue where sequelize fails, look at those issues.
https://github.com/sequelize/sequelize/issues/7344
https://github.com/sequelize/...
1
vote
3
answers
717
views
How to not allow to insert a new record if count of current records exceeds a specified limit
I have two tables as the following
team
`id` BIGINT PRIMARY KEY AUTO_INCREMENT,
`name` VARCHAR(255) NOT NULL,
`member_limit` INT NOT NULL
team_member
`id` BIGINT PRIMARY KEY AUTO_INCREMENT,
`team_id` ...
1
vote
0
answers
263
views
Mysql self Join query with Limit never terminates
I'm running an experiment with the query
Select Distinct table_1.id1, table_2.id1
FROM image as table_1, image as table_2
WHERE table_1.id2 = table_2.id2
LIMIT K;
When I run the query ...
0
votes
1
answer
106
views
updating n number of records mysql database
I want to update n number of records in table using a query like below, but it will return an error since in mysql, it is not allowed to use value after the limit key
update producedItem pi
inner ...
0
votes
1
answer
279
views
MySQL apply LIMIT and OFFSET to a selected table, rather than to the result set
I have 3 tables as below.
mysql> describe IDN_CONFIG_RESOURCE;
+---------------+--------------+------+-----+-------------------+-------+
| Field | Type | Null | Key | Default ...
0
votes
1
answer
69
views
Display Top X results for each unique value
I am trying to figure out how I can output any machine that has had the latest 3 backups be larger than 10GB. My SQL Table looks similar to the below table:
ComputerID | BackupImageName | ...
0
votes
1
answer
900
views
How does adding LIMIT work with Where conditions in mysql?
In my database, there is only one record which satisfies the condition iv_title = 'ball skills'.
Now I'm executing the following query :
SELECT
*
FROM
`imageAndVideo`
WHERE
`iv_title` = '...
1
vote
0
answers
23
views
Set Maximum Tables In A Database [duplicate]
I need to set up a MySQL database with a maximum number of tables which can be created in it.
For example, if I have my maximum at 5 tables for a single database, and someone attempts to create a 6th ...
1
vote
1
answer
682
views
Distinct result with row_id for limit query
There are 2 tables:
CREATE TABLE sample1 (
id int,
name varchar,
score int,
mode int
)
CREATE TABLE sample2 (
id int,
mode int
...
)
I need to select distinct name with MIN(score) and ...
3
votes
2
answers
25k
views
Limit left join for multiple rows
Since MySql doesn't support main alias reference in subquery is a bit challenging to create query with multiple rows where you have to limit rows of left join tables.
Let's overview simple example.
...
2
votes
2
answers
770
views
Predicting the primary keys exhaustion in MySQL based on rate of insertion
We are running out of primary keys for our table in production. We do not want that to occur again. So we need a mechanism to alert us when we are running out of primary keys based on the rate of ...
1
vote
0
answers
819
views
SQL Server Express 2017 database size limitation
I have a database hosted on SQL Server Express 2017. The size was small like 200MB. Today I have copied 24GB tables to the same database from external database hosted on different server.
The ...
0
votes
1
answer
208
views
MySQL logging max_questions resource
How would I know in MySQL if the user has exceeded his max_queries per hour?
I know that I can see this error on the client side, but I just want to know that before client is reporting to me, ...
0
votes
1
answer
5k
views
Limit groups of results based on a column value
I'm not sure I formulated the question properly, but anyway.
I have a table with level-2 comments, some of which, expectedly, have the same comment_parent column value. How do I make a SELECT query ...
1
vote
1
answer
48
views
What happens if I load last 10 rows then next 10 after other rows are inserted?
What if I had a PHP script that had a pagination that loads last 10 rows then page two loaded next 10 in DESC order, but before loading next 10 on page 2, other 10 rows were added to the table?
What ...
3
votes
2
answers
22k
views
Alternate to use LIMIT in subquery in mysql?
I have 2 tables, Resource and views and I'm trying to get the list of all the items from Resource table whose ran_resId don't match with the ran_resId of last 2 records of views table. I'm trying to ...
0
votes
1
answer
403
views
Does switching from INT to BIGINT entails significant downtime?
Hypothetically, if your INT column already has 4 billion rows, how long is the process of converting that column to BIGINT? I know this will depend on server resources but I just want to have a ...
1
vote
1
answer
390
views
Delete from table using FK columns, JOIN and LIMIT
This query below will never complete, since it always looks at the first 100,000 (user_type, user_ids). How can I write this to delete 100,000 records from the table with the FK reference (Product) to ...
14
votes
1
answer
13k
views
Why *not* ERROR: index row size xxxx exceeds maximum 2712 for index "foo"?
We have repeatedly seen failing attempts to index columns with values exceeding a maximum size. Postgres 10 has this kind of error message for it:
ERROR: index row size xxxx exceeds maximum 2712 for ...
20
votes
2
answers
24k
views
MongoDB terminates when it runs out of memory
I have the following configuration:
a host machine that runs three docker containers:
MongoDB
Redis
A program using the previous two containers to store data
Both Redis and MongoDB are used to ...
7
votes
2
answers
6k
views
Postgres slow query with order by, index and limit
I am trying to improve the performance of a postgres(9.6) query. Here is my schema and table contains about 60 million rows.
Column | Type | Modifiers
-------...
20
votes
5
answers
15k
views
SQL Server Error 8632 due to over 100,000 entries in WHERE clause
My problem (or at least the error message) is very similar to query processor ran out of internal resources - extremely long sql query.
My customer is working with an SQL select-query, containing a ...
2
votes
1
answer
161
views
Is there a server option which limits the amount of rows returned by a remote query?
I have an issue where a system on our network is making a query (select * from table) which might result in 0 to 70k rows being returned.
For large result sets, say around 50k, the calling system is ...
1
vote
1
answer
279
views
Is it possible to limit concurrent aggregations in Mongo?
When clients makes certain requests, our service sends aggregation queries to Mongo. Some of these aggregations take longer than others.
Usually this is fine, but occasionally multiple heavy ...
5
votes
1
answer
4k
views
Limits of applock in MS SQL Server
Microsoft SQL Server offers an arbitrary application-defined locking mechanism through the sp-getapplock command and related commands.
The key, or resource_name, is specified as a string, a varchar ...
5
votes
2
answers
39k
views
MySQL LIMIT within JOIN
I have an 1:m association.
symbols table has many rows in company_key_statistics table. company_key_statistics has column createdAt which is timestamp indicating when row has been created.
I need to ...
4
votes
1
answer
2k
views
PostgreSQL Size Quota on Table or Schema
How do one limit the size of a PostgreSQL table? (or schema)
Limit in either bytes or rows would be OK.
I'm starting to think that there's no easy and obvious solution.
I have a lot of identical ...
3
votes
1
answer
1k
views
MySQL 5.5 vs 5.6,5.7 above same database same query but different output, limit have duplicated ID
I am using Running same source code and same database for WordPress, only the mysql version is different. It make my pagination post have duplication.
Here is what I found out. Any idea how to solve ...