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Recommended SQL database design for tags or tagging [closed]
I've heard of a few ways to implement tagging; using a mapping table between TagID and ItemID (makes sense to me, but does it scale?), adding a fixed number of possible TagID columns to ItemID (seems like a bad idea), Keeping tags in a text column that's comma separated (sounds crazy but could work)...
Is there an SQLite equivalent to MySQL's DESCRIBE [table]?
...ed learning SQLite . It would be nice to be able to see the details for a table, like MySQL's DESCRIBE [table] . PRAGMA table_info [table] isn't good enough, as it only has basic information (for example, it doesn't show if a column is a field of some sort or not). Does SQLite have a way to do t...
Update a table using JOIN in SQL Server?
I want to update a column in a table making a join on other table e.g.:
11 Answers
11
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How to create relationships in MySQL
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If the tables are innodb you can create it like this:
CREATE TABLE accounts(
account_id INT NOT NULL AUTO_INCREMENT,
customer_id INT( 4 ) NOT NULL ,
account_type ENUM( 'savings', 'credit' ) NOT NULL,
balance FLOAT(...
How do you create a read-only user in PostgreSQL?
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Grant usage/select to a single table
If you only grant CONNECT to a database, the user can connect but has no other privileges. You have to grant USAGE on namespaces (schemas) and SELECT on tables and views individually like so:
GRANT CONNECT ON DATABASE...
How to force table cell content to wrap?
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Use table-layout:fixed in the table and word-wrap:break-word in the td.
See this example:
<html>
<head>
<style>
table {border-collapse:collapse; table-layout:fixed; width:310px;}
table td {border:soli...
Avoid duplicates in INSERT INTO SELECT query in SQL Server
I have the following two tables:
8 Answers
8
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Converting Select results into Insert script - SQL Server [closed]
... a variety of great features - including generating INSERT statements from tables.
Update: for SQL Server Management Studio 2012 (and newer), SSMS Toolpack is no longer free, but requires a modest licensing fee.
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Fastest way to count exact number of rows in a very large table?
I have come across articles that state that SELECT COUNT(*) FROM TABLE_NAME will be slow when the table has lots of rows and lots of columns.
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SQL query return data from multiple tables
...t 1 - Joins and Unions
This answer covers:
Part 1
Joining two or more tables using an inner join (See the wikipedia entry for additional info)
How to use a union query
Left and Right Outer Joins (this stackOverflow answer is excellent to describe types of joins)
Intersect queries (and how to re...