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Updating MySQL primary key
I have a table user_interactions with 4 columns:
3 Answers
3
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Is the primary key automatically indexed in MySQL?
...m/doc/refman/5.5/en/optimizing-primary-keys.html
The primary key for a table represents the column or set of columns
that you use in your most vital queries. It has an associated index,
for fast query performance
For MySQL 5.0 reference see: http://dev.mysql.com/doc/refman/5.0/en/mysql-ind...
Change limit for “Mysql Row size too large”
... the following to the my.cnf file under [mysqld] section.
innodb_file_per_table=1
innodb_file_format = Barracuda
ALTER the table to use ROW_FORMAT=COMPRESSED.
ALTER TABLE nombre_tabla
ENGINE=InnoDB
ROW_FORMAT=COMPRESSED
KEY_BLOCK_SIZE=8;
There is a possibility that the above sti...
How to get script of SQL Server data? [duplicate]
...analogous to the MySQL dump from SQL Server. I need to be able to pick the tables and export the schema and the data (or I can export the schema via SQL Server Management Studio and export the data separately somehow).
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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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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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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...
How to Vertical align elements in a div?
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This also works with inline-block and table-cell elements. If you are having issues with this, try adjusting line-height of the container element (i.e. context) since it is used in the vertical-align line box calculations.
– Alex W
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Is SHA-1 secure for password storage?
...ht now even with the "broken" hash functions MD5 and SHA-1.
About rainbow tables:
The "rainbow attack" is actually cost-sharing of a dictionary or brute force attack. It is a derivative from the time-memory trade-off first described by Hellman in 1980. Assuming that you have N possible passwords (...
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;
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