Questions tagged [database]
A database is an organized collection of data. It is the collection of schemas, tables, queries, reports, views, and other objects. The data is typically organized to model aspects of reality in a way that supports processes requiring information. Use this tag if you have questions about designing a database. If it is about a particular database management system, (e.g., MySQL), please use that tag instead.
database
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How does database indexing work? [closed]
Given that indexing is so important as your data set increases in size, can someone explain how indexing works at a database-agnostic level?
For information on queries to index a field, check out How ...
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How to import an SQL file using the command line in MySQL?
I have a .sql file with an export from phpMyAdmin. I want to import it into a different server using the command line.
I have a Windows Server 2008 R2 installation. I placed the .sql file on the C ...
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How to show tables in PostgreSQL?
What's the equivalent to show tables (from MySQL) in PostgreSQL?
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What is the "N+1 selects problem" in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries ...
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PostgreSQL "DESCRIBE TABLE"
How do you perform the equivalent of Oracle's DESCRIBE TABLE in PostgreSQL with psql command?
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Insert into ... values ( SELECT ... FROM ... )
I am trying to INSERT INTO a table using the input from another table. Although this is entirely feasible for many database engines, I always seem to struggle to remember the correct syntax for the ...
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What are the options for storing hierarchical data in a relational database?
Good Overviews
Generally speaking, you're making a decision between fast read times (for example, nested set) or fast write times (adjacency list). Usually, you end up with a combination of the ...
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Which version of PostgreSQL am I running?
I'm in a corporate environment (running Debian Linux) and didn't install it myself. I access the databases using Navicat or phpPgAdmin (if that helps). I also don't have shell access to the server ...
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How do I rename a MySQL database (change schema name)?
How do I quickly rename a MySQL database (change its schema name)?
Usually I just dump a database and re-import it with a new name. This is not an option for very big databases. Apparently RENAME {...
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Reset identity seed after deleting records in SQL Server
I have inserted records into a SQL Server database table. The table had a primary key defined and the auto increment identity seed is set to “Yes”. This is done primarily because in SQL Azure, each ...
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Optimistic vs. Pessimistic locking
I understand the differences between optimistic and pessimistic locking. Now, could someone explain to me when I would use either one in general?
And does the answer to this question change depending ...
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Database, Table and Column Naming Conventions? [closed]
Whenever I design a database, I always wonder if there is a best way of naming an item in my database. Quite often I ask myself the following questions:
Should table names be plural?
Should column ...
- 75.3k
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MyISAM versus InnoDB [closed]
I'm working on a projects which involves a lot of database writes, I'd say (70% inserts and 30% reads). This ratio would also include updates which I consider to be one read and one write. The reads ...
- 9,251
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What's the difference between identifying and non-identifying relationships?
I haven't been able to fully grasp the differences. Can you describe both concepts and use real world examples?
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Multiple Indexes vs Multi-Column Indexes
What is the difference between creating one index across multiple columns versus creating multiple indexes, one per column?
Are there reasons why one should be used over the other?
For example:
Create ...
- 75.3k