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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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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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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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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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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...
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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ALTER TABLE to add a composite primary key
...table you will get an error when trying to drop it. In some versions of mysql the error message there was malformed (as of 5.5.17, this error message is still
alter table parent drop column id;
ERROR 1025 (HY000): Error on rename of
'./test/#sql-a04_b' to './test/parent' (errno: 150).
If you wa...
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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Querying data by joining two tables in two database on different servers
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Once the link is established, you can also use OPENQUERY to execute a SQL statement on the remote server and transfer only the data back to you. This can be a bit faster, and it will let the remote server optimize your query. If you cache the data in a temporary (or in-memory) table on DB1 in...