database-performance

相关标签：javascript jquery android 多少钱 iPhone

PostgreSQL: Why does this simple query not use the index?

I have a table t with a column c, which is an int and has a btree index on it. Why does the following query not utilize this index?[详细]

2023-02-08 10:32 分类：问答
Performance on updates using cursor in PostgreSQL

I would like to know the performance difference in updating a table using the following method: UPDATE films SET kind = \'Dramatic\' WHERE CURRENT OF c_films;[详细]

2023-02-05 20:48 分类：问答
How many MySql queries/second can be handled by a server?

I\'ve started developing a browser (database) game. My question is how many queries can a regular hosting handle (when I mean regular, I mean a shared hosting you cand find for about 7$/month).[详细]

2023-02-02 09:04 分类：问答
Is it faster to read from fixed-width columns in SQLite?

Would it generally be faster to read from a table where there are no varchar or other variable length data stored? In MySQL, this is faster because it can calculate exactly wh开发者_如何转开发ere a ro[详细]

2023-01-30 06:12 分类：问答
Database design - question about efficiency (and general design quality)

I fear I don\'t know what I\'m doing. 1: I have a table called ticket which has a column called total. When the total is updated I want to keep a record of it (old total, etc), so I decided to remove[详细]

2023-01-18 09:37 分类：问答
Selectively deleting large amounts data from Sybase table

Using Sybase ASE 15 for this - I have about a large amount of rows (up to 10 mil) to delete from a table on a regular basis, but I want to keep a selection of the latest added data to the table, so th[详细]

2023-01-15 21:04 分类：问答
MySQL - How do I efficiently get the row with the lowest ID?

Is there a faster way to update the oldest row of a MySQL table that matches a certain condition than using ORDER BY id LIMIT 1 as in the following query?[详细]

2023-01-15 12:11 分类：问答
What's TOO BIG for a database?

I have a buddy who runs a web app for people listing cars for sale. There are a few thousand clients who use it, and each client has hundreds and sometimes thousands of rows in the database (some have[详细]

2023-01-15 11:51 分类：问答
mysql simple aggregate of subquery results is slow

I\'m trying to \'bin\' all of my customers based on the number of items purchased, and display the counts of each bin.I\'m trying to see how many people(account_id) purchased one item, how many purcha[详细]

2023-01-13 04:56 分类：问答
Which database (DBMS) can best handle large tables?

I also have a very large table in SQL Server (2008 R2 Developer Edition) that is having some performance problems.[详细]

2023-01-07 09:12 分类：问答