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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...
MySQL case insensitive select
...in did mention collate was better) We had historical data moved into mysql table which broke legacy logic because of certain column values having insensitive case. We needed to know the difference between "GE1234" and "ge1234", they needed to be unique and stay logged that way. We set our column in ...
How do I drop a foreign key constraint only if it exists in sql server?
I can drop a table if it exists using the following code but do not know how to do the same with a constraint:
10 Answers
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How do I make a composite key with SQL Server Management Studio?
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Open the design table tab
Highlight your two INT fields (Ctrl/Shift+click on the grey blocks in the very first column)
Right click -> Set primary key
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How to import an excel file in to a MySQL database
... Note that this procedure requires that you first create the table, with the appropriate fields.
– LarsH
Mar 24 '16 at 15:00
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MySQL Update Inner Join tables query
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Update:
Since you said the query yielded a syntax error, I created some tables that I could test it against and confirmed that there is no syntax error in my query:
mysql> create table business (business_id int unsigned primary key auto_increment, mapx varchar(255), mapy varchar(255)) engine=...
PostgreSQL: Can you create an index in the CREATE TABLE definition?
I want to add indexes to some of the columns in a table on creation. Is there are way to add them to the CREATE TABLE definition or do I have to add them afterward with another query?
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How to get multiple counts with one SQL query?
...(case when level = 'personal' then 1 else 0 end) AS PersonalCount
FROM yourtable
GROUP BY distributor_id
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Querying data by joining two tables in two database on different servers
There are two tables in two different databases on different servers, I need to join them so as to make few queries. What options do I have? What should I do?
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Newline in markdown table?
I have the following cells in a markdown table:
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