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SQL/mysql - Select distinct/UNIQUE but return all columns?
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You're looking for a group by:
select *
from table
group by field1
Which can occasionally be written with a distinct on statement:
select distinct on field1 *
from table
On most platforms, however, neither of the above will work because the behavior on the other co...
How Can I Set the Default Value of a Timestamp Column to the Current Timestamp with Laravel Migratio
... use DB::raw() to set CURRENT_TIMESTAMP as a default value for a column:
$table->timestamp('created_at')->default(DB::raw('CURRENT_TIMESTAMP'));
This works flawlessly on every database driver.
New shortcut
As of Laravel 5.1.25 (see PR 10962 and commit 15c487fe) you can use the new useCurr...
How to take MySQL database backup using MySQL Workbench?
...different way as given below-
Q.1) Backup file(.sql) contains both Create Table statements and Insert into Table Statements
ANS:
Select Start Export Option
Q.2) Backup file(.sql) contains only Create Table Statements, not Insert into Table statements for all tables
ANS:
Select Skip Table Da...
MYSQL import data from csv using LOAD DATA INFILE
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You can use LOAD DATA INFILE command to import csv file into table.
Check this link MySQL - LOAD DATA INFILE.
LOAD DATA LOCAL INFILE 'abc.csv' INTO TABLE abc
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\r\n'
IGNORE 1 LINES
(col1, col2, col3, col4, col5...);
For...
SQL Server: Get table primary key using sql query [duplicate]
I want to get a particular table's primary key using SQL query for SQL Server database.
10 Answers
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Can table columns with a Foreign Key be NULL?
I have a table which has several ID columns to other tables.
7 Answers
7
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Unable to update the EntitySet - because it has a DefiningQuery and no element exis
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Entity Set is mapped from Database view
A custom Database query
Database table doesn't have a primary key
After doing so, you may still need to update in the Entity Framework designer (or alternatively delete the entity and then add it) before you stop getting the error.
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Define variable to use with IN operator (T-SQL)
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DECLARE @MyList TABLE (Value INT)
INSERT INTO @MyList VALUES (1)
INSERT INTO @MyList VALUES (2)
INSERT INTO @MyList VALUES (3)
INSERT INTO @MyList VALUES (4)
SELECT *
FROM MyTable
WHERE MyColumn IN (SELECT Value FROM @MyList)
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@UniqueConstraint annotation in Java
...@UniqueConstraint annotation is for annotating multiple unique keys at the table level, which is why you get an error when applying it to a field.
References (JPA TopLink):
@UniqueConstraint
@Column
share
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SQL - find records from one table which don't exist in another
I've got the following two SQL tables (in MySQL):
8 Answers
8
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