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Find rows that have the same value on a column in MySQL
In a [member] table, some rows have the same value for the email column.
8 Answers
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Print only?
... but I had two troubles with it: for one if any of the element's parents established its own relative/absolute positioning the content would still be offset unless I used position:fixed instead. However, Chrome and Safari would also truncate content, especially after the first page. So my final work...
Using IQueryable with Linq
...tabase, with many ORM systems, you have the option of fetching data from a table in two ways, one which returns IEnumerable<T>, and one which returns an IQueryable<T>. Say, for example, you have a Products table, and you want to get all of the products whose cost is >$25.
If you do:...
When to add what indexes in a table in Rails
... end of the index.
If you have a has_many :through relationship, your join table should have a unique index on both properties involved in the join as a compound key.
If you fetch a record directly using a unique identifier such as username or email, that should be a unique index.
If you fetch sets ...
Why use multiple columns as primary keys (composite primary key)
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Another example of compound primary keys are the usage of Association tables. Suppose you have a person table that contains a set of people and a group table that contains a set of groups. Now you want to create a many to many relationship on person and group. Meaning each person can belong t...
UITableView - scroll to the top
In my table view I have to scroll to the top. But I cannot guarantee that the first object is going to be section 0, row 0. May be that my table view will start from section number 5.
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What is the difference between a schema and a table and a database?
...bably a n00blike (or worse) question. But I've always viewed a schema as a table definition in a database. This is wrong or not entirely correct. I don't remember much from my database courses.
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Return number of rows affected by UPDATE statements
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CREATE PROCEDURE UpdateTables
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
DECLARE @RowCount1 INTEGER
DECLARE @RowCount2 INTEGER
DECLARE @RowCount3...
Count Rows in Doctrine QueryBuilder
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The most portable way is to do $qb->select($qb->expr()->count('account.id'))
– webbiedave
May 23 '16 at 22:04
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Zip lists in Python
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len(result[0]) wont work. 'zip' object is not subscriptable
– GilbertS
Feb 23 at 16:23
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