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Is a view faster than a simple query?
...y referenced by another query as the optimizer will use them in place of a table reference when appropriate.
Again, the documentation:
The indexed view can be used in a query execution in two ways. The query can reference the indexed view directly, or, more importantly, the query optimizer c...
How to convert a string or integer to binary in Ruby?
...
Picking up on bta's lookup table idea, you can create the lookup table with a block. Values get generated when they are first accessed and stored for later:
>> lookup_table = Hash.new { |h, i| h[i] = i.to_s(2) }
=> {}
>> lookup_table[1]...
Do I need to create indexes on foreign keys on Oracle?
I have a table A and a table B . A has a foreign key to B on B 's primary key, B_ID .
7 Answers
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Quick easy way to migrate SQLite3 to MySQL? [closed]
...te_sequence
CREATE UNIQUE INDEX
are not used in MySQL
SQLite uses CREATE TABLE/INSERT INTO "table_name" and MySQL uses CREATE TABLE/INSERT INTO table_name
MySQL doesn't use quotes inside the schema definition
MySQL uses single quotes for strings inside the INSERT INTO clauses
SQLite and MySQL have...
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
...
Log all queries in mysql
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Is it possible to log queries over 1 particuarl db / table only?
– Temujin
Aug 4 '12 at 16:08
2
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How to update column with null value
...
No special syntax:
CREATE TABLE your_table (some_id int, your_column varchar(100));
INSERT INTO your_table VALUES (1, 'Hello');
UPDATE your_table
SET your_column = NULL
WHERE some_id = 1;
SELECT * FROM your_table WHERE your_column IS NULL;
+---...
Equivalent of LIMIT and OFFSET for SQL Server?
... ROW_NUMBER() OVER (ORDER BY SortCol1, SortCol2, ...) AS RowNum
FROM Table
WHERE <whatever>
)
SELECT *
FROM Results_CTE
WHERE RowNum >= @Offset
AND RowNum < @Offset + @Limit
The advantage here is the parameterization of the offset and limit in case you decide to change your p...
How to show the last queries executed on MySQL?
...ontrol this option globally at runtime:
Execute SET GLOBAL log_output = 'TABLE';
Execute SET GLOBAL general_log = 'ON';
Take a look at the table mysql.general_log
If you prefer to output to a file instead of a table:
SET GLOBAL log_output = "FILE"; the default.
SET GLOBAL general_log_file = ...
Rails migration: t.references with alternative name?
So I have a create_table like this for Courses at a School:
5 Answers
5
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