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Entity Attribute Value Database vs. strict Relational Model Ecommerce
...uld be domain models. Sort of like a serialization, but you could use SQL selects on indexed text fields. No multiple selects per record. All the "cost" happens in RAM.
– Zachary Scott
Jun 15 '10 at 3:06
...
Get table column names in MySQL?
...DESCRIBE my_table;
Or in newer versions you can use INFORMATION_SCHEMA:
SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_SCHEMA = 'my_database' AND TABLE_NAME = 'my_table';
Or you can use SHOW COLUMNS:
SHOW COLUMNS FROM my_table;
...
Can you create nested WITH clauses for Common Table Expressions?
..., the form of the statement you are looking for would be
WITH x AS
(
SELECT * FROM MyTable
),
y AS
(
SELECT * FROM x
)
SELECT * FROM y
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GROUP BY with MAX(DATE) [duplicate]
... to your group by clause, otherwise you need to rethink your query.
Try:
SELECT t.Train, t.Dest, r.MaxTime
FROM (
SELECT Train, MAX(Time) as MaxTime
FROM TrainTable
GROUP BY Train
) r
INNER JOIN TrainTable t
ON t.Train = r.Train AND t.Time = r.MaxTime
...
Shortcuts in Objective-C to concatenate NSStrings
...%@", three, two, one]; technique seems the most elegant. It should be the selected answer.
– ekillaby
Feb 21 '14 at 19:39
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Reason for Column is invalid in the select list because it is not contained in either an aggregate f
...c
1 def
1 ghi
2 jkl
2 mno
2 pqr
And I do the following query:
SELECT a, b
FROM T
GROUP BY a
The output should have two rows, one row where a=1 and a second row where a=2.
But what should the value of b show on each of these two rows? There are three possibilities in each case, and no...
How to get all columns' names for all the tables in MySQL?
...
select * from information_schema.columns
where table_schema = 'your_db'
order by table_name,ordinal_position
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impro...
How to declare a variable in MySQL?
...at has not been
initialized, it has a value of NULL and a type of string.
SELECT @var_any_var_name
You can initialize a variable using SET or SELECT statement:
SET @start = 1, @finish = 10;
or
SELECT @start := 1, @finish := 10;
SELECT * FROM places WHERE place BETWEEN @start AND @finish...
SQL order string as number
...u can't do that then cast your column value to an integer explicitly with
select col from yourtable
order by cast(col as unsigned)
or implicitly for instance with a mathematical operation which forces a conversion to number
select col from yourtable
order by col + 0
BTW MySQL converts strings...
Why .NET String is immutable? [duplicate]
... before StringBuilder becomes more efficient than the equivalent series of concatenations, with their inherent construction).
It would be a disadvantage if mutability was part of the purpose of an object (who'd want to be modeled by an Employee object whose salary could never ever change) though so...