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What are the possible values of the Hibernate hbm2ddl.auto configuration and what do they do
...this option is used it does not drop the whole schema instead it drops the tables whose mappings are available while running this. For example if a database with Schema S has A, B, C tables and java code has mappings for A and B only then Hibernate will not drop the table C.
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Update or Insert (multiple rows and columns) from subquery in PostgreSQL
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For the UPDATE
Use:
UPDATE table1
SET col1 = othertable.col2,
col2 = othertable.col3
FROM othertable
WHERE othertable.col1 = 123;
For the INSERT
Use:
INSERT INTO table1 (col1, col2)
SELECT col1, col2
FROM othertable
You don't ...
Better way to set distance between flexbox items
...llapsing margins.
Flexbox doesn't have anything akin to border-spacing for tables (except for CSS property gap which isn't supported in Safari, caniuse)
Therefore achieving what you are asking for is a bit more difficult.
In my experience, the "cleanest" way that doesn't use :first-child/:last-chil...
MySQL - How to select data by string length
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select * from table order by length(column);
Documentation on the length() function, as well as all the other string functions, is available here.
share
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How to remove/ignore :hover css style on touch devices
...e the :hover CSS does not make sense, and it can even be disturbing if a tablet triggers it on click/tap because then it might stick until the element loses focus. To be honest, I don't know why touch devices feel the need to trigger :hover in first place - but this is reality, so this problem i...
Is a Java hashmap search really O(1)?
...r with average-case (expected) runtime. The former is indeed O(n) for hash tables in general (i.e. not using a perfect hashing) but this is rarely relevant in practice.
Any dependable hash table implementation, coupled with a half decent hash, has a retrieval performance of O(1) with a very small f...
How should I choose an authentication library for CodeIgniter? [closed]
... set
Very good documentation
Simple and elegant database design (just 4 DB tables)
Most features are optional and easily configured
Language file support
reCAPTCHA supported
Hooks into CI's validation system
Activation emails
Login with email, username or both (configurable)
Unactivated accounts aut...
Row Offset in SQL Server
... SELECT col1, col2, ROW_NUMBER() OVER (ORDER BY ID) AS RowNum
FROM MyTable
) AS MyDerivedTable
WHERE MyDerivedTable.RowNum BETWEEN @startRow AND @endRow
SQL Server 2000
Efficiently Paging Through Large Result Sets in SQL Server 2000
A More Efficient Method for Paging Through Large Result S...
SQL: capitalize first letter only [duplicate]
...a inside column? If its data you've to change, then use this:
UPDATE [yourtable]
SET word=UPPER(LEFT(word,1))+LOWER(SUBSTRING(word,2,LEN(word)))
If you just wanted to change it only for displaying and do not need the actual data in table to change:
SELECT UPPER(LEFT(word,1))+LOWER(SUBSTRING(word...
Specify custom Date format for colClasses argument in read.table/read.csv
... way to specify the Date format when using the colClasses argument in read.table/read.csv?
4 Answers
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