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How to annotate MYSQL autoincrement field with JPA annotations
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To use a MySQL AUTO_INCREMENT column, you are supposed to use an IDENTITY strategy:
@Id @GeneratedValue(strategy=GenerationType.IDENTITY)
private Long id;
Which is what you'd get when using AUTO with MySQL:
@Id @GeneratedValue(strategy=GenerationType.AUTO)
private Long id;
Which is a...
Why does MYSQL higher LIMIT offset slow the query down?
...ecords. It needs to check and count each record on its way.
Assuming that id is a PRIMARY KEY of a MyISAM table, you can speed it up by using this trick:
SELECT t.*
FROM (
SELECT id
FROM mytable
ORDER BY
id
LIMIT 10000, 30
) q
JOIN ...
How do I UPDATE from a SELECT in SQL Server?
..._Table AS Table_A
INNER JOIN Other_Table AS Table_B
ON Table_A.id = Table_B.id
WHERE
Table_A.col3 = 'cool'
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INSERT IF NOT EXISTS ELSE UPDATE?
...ang_conflict.html.
You want something like:
insert or replace into Book (ID, Name, TypeID, Level, Seen) values
((select ID from Book where Name = "SearchName"), "SearchName", ...);
Note that any field not in the insert list will be set to NULL if the row already exists in the table. This is why ...
Should I make HTML Anchors with 'name' or 'id'?
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According to the HTML 5 specification, 5.9.8 Navigating to a fragment identifier:
For HTML documents (and the text/html MIME type), the following processing model must be followed to determine what the indicated part of the document is.
Parse the URL, and let fragid be the <fr...
Real life example, when to use OUTER / CROSS APPLY in SQL
... FROM sys.parameters pa
WHERE pa.object_id = pr.object_id
ORDER BY pr.name) pa
ORDER BY pr.name,
pa.name
2) Calling a Table Valued Function for each row in the outer query
SELECT *
FROM sys.dm_exec_query_stats AS qs
CROSS APPLY s...
How to get next/previous record in MySQL?
Say I have records with IDs 3,4,7,9 and I want to be able to go from one to another by navigation via next/previous links. The problem is, that I don't know how to fetch record with nearest higher ID.
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What is the purpose of Android's tag in XML layouts?
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<merge/> is useful because it can get rid of unneeded ViewGroups, i.e. layouts that are simply used to wrap other views and serve no purpose themselves.
For example, if you were to <include/> a layout from another file without using merge, the two files mig...
How to put more than 1000 values into an Oracle IN clause [duplicate]
...000 items in a static IN clause? I have a comma delimited list of many of IDs that I want to use in an IN clause, Sometimes this list can exceed 1000 items, at which point Oracle throws an error. The query is similar to this...
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Check if key exists and iterate the JSON array using Python
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import json
jsonData = """{"from": {"id": "8", "name": "Mary Pinter"}, "message": "How ARE you?", "comments": {"count": 0}, "updated_time": "2012-05-01", "created_time": "2012-05-01", "to": {"data": [{"id": "1543", "name": "Honey Pinter"}]}, "type": "status", "i...