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What is the error “Every derived table must have its own alias” in MySQL?
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Every derived table (AKA sub-query) must indeed have an alias. I.e. each query in brackets must be given an alias (AS whatever), which can the be used to refer to it in the rest of the outer query.
SELECT ID FROM (
SELECT ID, msisdn F...
Querying DynamoDB by date
...ndary indexes can either be global, meaning that the index spans the whole table across hash keys, or local meaning that the index would exist within each hash key partition, thus requiring the hash key to also be specified when making the query.
For the use case in this question, you would want to...
Alter table add multiple columns ms sql
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You need to remove the brackets
ALTER TABLE Countries
ADD
HasPhotoInReadyStorage bit,
HasPhotoInWorkStorage bit,
HasPhotoInMaterialStorage bit,
HasText bit;
share
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Difference between EXISTS and IN in SQL?
... as a way to avoid counting:
--this statement needs to check the entire table
select count(*) from [table] where ...
--this statement is true as soon as one match is found
exists ( select * from [table] where ... )
This is most useful where you have if conditional statements, as exists can be ...
Is a Python dictionary an example of a hash table?
...looking up "values" of any type. Is this implemented internally as a hash table? If not, what is it?
4 Answers
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How to align input forms in HTML
...tion does not appear to work. The input elements are not left-aligned. The table solution below works.
– johny why
Jan 24 '14 at 18:18
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How do I update a Linq to SQL dbml file?
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There are three ways to keep the model in sync.
Delete the modified tables from the designer, and drag them back onto the designer surface from the Database Explorer. I have found that, for this to work reliably, you have to:
a. Refresh the database schema in the Database Explorer (right-c...
Meaning of Open hashing and Closed hashing
... us the index (aka. address) at which an object will be stored in the hash table is not completely determined by its hash code. Instead, the index may vary depending on what's already in the hash table.
The "closed" in "closed hashing" refers to the fact that we never leave the hash table; every...
SQL - Update multiple records in one query
I have table - config .
Schema:
config_name | config_value
9 Answers
9
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horizontal scrollbar on top and bottom of table
I've a very large table on my page. So I decided to put a horizontal scrollbar on the bottom of the table. But I would like this scrollbar to be also on top on the table.
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