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Jdbctemplate query for string: EmptyResultDataAccessException: Incorrect result size: expected 1, ac
...n I just ask why 'Now the correct way is not to catch this exception', considering if you're using queryForObject? What would be wrong with catching an exception in the case of queryForObject? Thanks :)
– Michael Stokes
Dec 12 '16 at 3:49
...
Trigger a button click with JavaScript on the Enter key in a text box
...t to trigger the button's click event when the Enter key is pressed inside the text box?
30 Answers
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Drop a temporary table if it exists
... IF EXISTS ##CLIENTS_KEYWORD
On previous versions you can use
IF OBJECT_ID('tempdb..##CLIENTS_KEYWORD', 'U') IS NOT NULL
/*Then it exists*/
DROP TABLE ##CLIENTS_KEYWORD
CREATE TABLE ##CLIENTS_KEYWORD
(
client_id INT
)
You could also consider truncating the table instead rather than dropping ...
how to add records to has_many :through association in rails
...mer.new(params[:customer])
@cust.houses << House.find(params[:house_id])
Or when creating a new house for a customer:
@cust = Customer.new(params[:customer])
@cust.houses.create(params[:house])
You can also add via ids:
@cust.house_ids << House.find(params[:house_id])
...
Rails raw SQL example
...
side note: records_array will be of different types for different database adapters. If you're using PG, it will be an instance of PG::Result, not Array.
– tybro0103
Jan 14 '14 at 17:28
...
Remove Primary Key in MySQL
...erty before dropping the key:
ALTER TABLE user_customer_permission MODIFY id INT NOT NULL;
ALTER TABLE user_customer_permission DROP PRIMARY KEY;
Note that you have a composite PRIMARY KEY which covers all three columns and id is not guaranteed to be unique.
If it happens to be unique, you can m...
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...em in useful detail.
In general you must choose between two options:
Individual insert/update operations in a retry loop; or
Locking the table and doing batch merge
Individual row retry loop
Using individual row upserts in a retry loop is the reasonable option if you want many connections concurre...
In CMake, how can I test if the compiler is Clang?
...
A reliable check is to use the CMAKE_<LANG>_COMPILER_ID variables. E.g., to check the C++ compiler:
if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
# using Clang
elseif (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
# using GCC
elseif (CMAKE_CXX_COMPILER_ID STREQUAL "Intel")
# using ...
How to pull a random record using Django's ORM?
...anager):
def random(self):
count = self.aggregate(count=Count('id'))['count']
random_index = randint(0, count - 1)
return self.all()[random_index]
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Update multiple rows in same query using PostgreSQL
... as c(column_b, column_a, column_c)
where c.column_b = t.column_b;
sql fiddle demo
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