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There can be only one auto column
...n I added primary key as below it started working:
CREATE TABLE book (
id INT AUTO_INCREMENT NOT NULL,
accepted_terms BIT(1) NOT NULL,
accepted_privacy BIT(1) NOT NULL,
primary key (id)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
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How to link to apps on the app store
I am creating a free version of my iPhone game. I want to have a button inside the free version that takes people to the paid version in the app store. If I use a standard link
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.NET unique object identifier
Is there a way of getting a unique identifier of an instance?
11 Answers
11
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MySQL Orderby a number, Nulls last
...to DESC:
SELECT * FROM tablename WHERE visible=1 ORDER BY -position DESC, id DESC
It is essentially the inverse of position DESC placing the NULL values last but otherwise the same as position ASC.
A good reference is here http://troels.arvin.dk/db/rdbms#select-order_by
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Add Foreign Key to existing table
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To add a foreign key (grade_id) to an existing table (users), follow the following steps:
ALTER TABLE users ADD grade_id SMALLINT UNSIGNED NOT NULL DEFAULT 0;
ALTER TABLE users ADD CONSTRAINT fk_grade_id FOREIGN KEY (grade_id) REFERENCES grades(id);
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How do I search an SQL Server database for a string?
...R(4000),
@ExactMatch BIT = 0
AS
SET NOCOUNT ON
DECLARE @Temp TABLE(RowId INT IDENTITY(1,1), SchemaName sysname, TableName sysname, ColumnName SysName, DataType VARCHAR(100), DataFound BIT)
INSERT INTO @Temp(TableName,SchemaName, ColumnName, DataType)
SELECT C.Table_Name,C.TABLE_SCHEM...
Why (0-6) is -6 = False? [duplicate]
...CPython and you shouldn't rely on this. For instance, PyPy implemented the id of integer to return itself, so (0-6) is -6 is always true even if they are "different objects" internally; it also allows you to configure whether to enable this integer caching, and even set the lower and upper bounds. B...
pass string parameter in an onclick function
... answered Mar 10 '12 at 2:41
daviddavid
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How to check if an int is a null
...er to be able to be null, you need to use Integer instead of int.
Integer id;
String name;
public Integer getId() { return id; }
Besides the statement if(person.equals(null)) can't be true, because if person is null, then a NullPointerException will be thrown. So the correct expression is if (pe...
Foreign Key naming scheme
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If the foreign key points to a candidate key on the second table rather than a primary key, then you'd probably use a third segment to the name to qualify this. It's an unusual situation to be in, and not one you'd typically design in from scratch, so I didn't...