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What are the First and Second Level caches in Hibernate?
...wont process one transaction many
times. Mainly it reduces the number of SQL queries it needs to
generate within a given transaction. That is instead of updating after
every modification done in the transaction, it updates the transaction
only at the end of the transaction.
1.2) Second-lev...
Why do you create a View in a database?
... users have the ability to run their own queries (through some interactive SQL program or writing their own scripts), they can run select * from customer which gives them access to everything. If you give them access to the view and not the table, they cannot access fields that aren't in the view.
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Postgresql SELECT if string contains
So I have a in my Postgresql:
5 Answers
5
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Query grants for a table in postgres
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\z mytable from psql gives you all the grants from a table, but you'd then have to split it up by individual user.
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How to list records with date from the last 10 days?
Does this work on PostgreSQL?
6 Answers
6
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How to do a batch insert in MySQL
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From the MySQL manual
INSERT statements that use VALUES
syntax can insert multiple rows. To do
this, include multiple lists of column
values, each enclosed within
parentheses and separated by commas.
Example:
INSERT INTO...
“’” showing on page instead of “ ' ”
...set the encoding of the table when you create it.
You're most likely using SQL Server, but here is some MySQL code (copied from this article):
CREATE DATABASE db_name CHARACTER SET utf8;
CREATE TABLE tbl_name (...) CHARACTER SET utf8;
If your table is however already UTF-8, then you need to take a ...
If string is empty then return some default value
... is not empty.
For example
@user.address.or User.make_a_long_and_painful_SQL_query_here
would make extra work even if address is not empty. Maybe you could update that a bit (sorry about confusing one-liner, trying to keep it short):
class String
def or what = ""
self.strip.empty? ? block...
What is the maximum number of characters that nvarchar(MAX) will hold?
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From char and varchar (Transact-SQL)
varchar [ ( n | max ) ]
Variable-length, non-Unicode character
data. n can be a value from 1 through
8,000. max indicates that the
maximum storage size is 2^31-1 bytes.
The storage size is the actual length
of data ente...
What are '$$' used for in PL/pgSQL
Being completely new to PL/pgSQL , what is the meaning of double dollar signs in this function :
2 Answers
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