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How to create id with AUTO_INCREMENT on Oracle?
...acle 11g. However, you can model it easily with a sequence and a trigger:
Table definition:
CREATE TABLE departments (
ID NUMBER(10) NOT NULL,
DESCRIPTION VARCHAR2(50) NOT NULL);
ALTER TABLE departments ADD (
CONSTRAINT dept_pk PRIMARY KEY (ID));
CREATE SEQUENCE dept_seq STA...
How to select multiple rows filled with constants?
Selecting constants without referring to a table is perfectly legal in an SQL statement:
15 Answers
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Understanding garbage collection in .NET
...ow. The second duty is however completely invisible. It also generates a table that describes how the local variables inside the method body are used. That table has an entry for each method argument and local variable with two addresses. The address where the variable will first store an object ...
How can I get the SQL of a PreparedStatement?
...ke this:
org.hsqldb.jdbc.JDBCPreparedStatement@7098b907[sql=[INSERT INTO
TABLE_NAME(COLUMN_NAME, COLUMN_NAME, COLUMN_NAME) VALUES(?, ?, ?)],
parameters=[[value], [value], [value]]]
Now I've created a method (Java 8), which is using regex to extract both query and values and put them into map:
p...
How can I hash a password in Java?
...id SecretKeyFactory", ex);
}
}
/**
* Hash a password in an immutable {@code String}.
*
* <p>Passwords should be stored in a {@code char[]} so that it can be filled
* with zeros after use instead of lingering on the heap and elsewhere.
*
* @deprecated Use {@link #...
HTML colspan in CSS
...
Tables are structural elements and just because using colspan changes its appearance does not mean it's not. CSS is used to style elements and not change the structure. The W3C discusses table structure here: w3.org/TR/h...
Tools for making latex tables in R [closed]
On general request, a community wiki on producing latex tables in R. In this post I'll give an overview of the most commonly used packages and blogs with code for producing latex tables from less straight-forward objects. Please feel free to add any I missed, and/or give tips, hints and little trick...
What are naming conventions for MongoDB?
... here. And after so many decades there is still no agreement whether RDBMS tables should be named singular or plural...
MongoDB speaks JavaScript, so utilize JS naming conventions of camelCase.
MongoDB official documentation mentions you may use underscores, also built-in identifier is named _id (bu...
What columns generally make good indexes?
...portant role in query optimization and searching the results speedily from tables. So it is most important step to select which columns to be indexed. There are two major places where we can consider indexing: columns referenced in the WHERE clause and columns used in JOIN clauses. In short, such co...
What's the difference between :: (double colon) and -> (arrow) in PHP?
...ate and delete methods, since you can set the return value to the inserted table id and then use the constructor to instantiate the object by the row id.
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