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What are the use cases of Graph-based Databases (http://neo4j.org/)? [closed]
...traversals in a graph database, but that would be quite complex queries in SQL.
The main advantages of the graph model were rapid development time and flexibility. We could quickly add new functionality without impacting existing deployments. If a potential customer wanted to import some of their o...
Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
I want to create a database which does not exist through JDBC. Unlike MySQL, PostgreSQL does not support create if not exists syntax. What is the best way to accomplish this?
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How to create Temp table with SELECT * INTO tempTable FROM CTE Query
I have a MS SQL CTE query from which I want to create a temporary table. I am not sure how to do it as it gives an Invalid Object name error.
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How to get the first and last date of the current year?
Using SQL Server 2000, how can I get the first and last date of the current year?
18 Answers
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Select something that has more/less than x character
... it's possible to select something that has more/less than x characters in SQL.
4 Answers
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Return 0 if field is null in MySQL
In MySQL, is there a way to set the "total" fields to zero if they are NULL?
5 Answers
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Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign
...the issue. Removing this section and keeping the rest will still print the SQLite error being generated, which will note the column that has the problem.
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When and why are database joins expensive?
...x strategy is available to the optimiser.
I used to be smarter than the MSSQL optimiser. That changed two versions ago. Now it generally teaches me. It is, in a very real sense, an expert system, codifying all the wisdom of many very clever people in a domain sufficiently closed that a rule-based s...
Sqlite primary key on multiple columns
What is the syntax for specifying a primary key on more than 1 column in SQLITE ?
9 Answers
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ActiveRecord: List columns in table from console
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If you are comfortable with SQL commands, you can enter your app's folder and run rails db, which is a brief form of rails dbconsole. It will enter the shell of your database, whether it is sqlite or mysql.
Then, you can query the table columns using...