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ORA-00054: resource busy and acquire with NOWAIT specified or timeout expired
Why am I getting this database error when I update a table?
14 Answers
14
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First-time database design: am I overengineering? [closed]
...ds. Unless you are talking about well over a million records in your main tables you seem to be on track to having a sufficiently mainstream design that performance will not be an issue on reasonable hardware.
That said, and this relates to your question 3, with the start you have you probably s...
Rails: Using greater than/less than with a where statement
...non discrete values or columns where you can't use the + 1 strategy.
Arel table
If you want to get fancy you can make use of the Arel::Table.
User.where(User.arel_table[:id].gt(200))
will generate the SQL
"SELECT `users`.* FROM `users` WHERE (`users`.`id` > 200)"
The specifics are as foll...
Can I create a named default constraint in an add column statement in SQL Server?
In SQL Server, I have a new column on a table:
4 Answers
4
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Is there a way to get a collection of all the Models in your Rails app?
...
ActiveRecord::Base.connection.tables.map do |model|
model.capitalize.singularize.camelize
end
will return
["Article", "MenuItem", "Post", "ZebraStripePerson"]
Additional information If you want to call a method on the object name without model:stri...
How do I handle too long index names in a Ruby on Rails ActiveRecord migration?
...an unique index that gets created from the foreign keys of four associated tables:
9 Answers
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Why do I get a “Null value was assigned to a property of primitive type setter of” error message whe
...he solution is replace primitive type with primitive wrapper class in your tableName.java file.
Such as:
@Column(nullable=true, name="client_os_id")
private Integer client_os_id;
public int getClient_os_id() {
return client_os_id;
}
public void setClient_os_id(int clientOsId) {
client_os_...
TSQL Pivot without aggregate function
I have a table like this...
9 Answers
9
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MYSQL Dump only certain rows
...t dumps everything. How can I get mysqldump to only dump certain rows of a table?
3 Answers
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Get the last inserted row ID (with SQL statement) [duplicate]
I want to get the new created ID when you insert a new record in table.
3 Answers
3
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