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Disable ONLY_FULL_GROUP_BY
...ove ONLY_FULL_GROUP_BY from mysql console
mysql > SET GLOBAL sql_mode=(SELECT REPLACE(@@sql_mode,'ONLY_FULL_GROUP_BY',''));
you can read more here
Solution 2: Remove ONLY_FULL_GROUP_BY from phpmyadmin
Open phpmyadmin & select localhost
Click on menu Variables & scroll down for sq...
Convert a string to int using sql query
...
You could use CAST or CONVERT:
SELECT CAST(MyVarcharCol AS INT) FROM Table
SELECT CONVERT(INT, MyVarcharCol) FROM Table
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Difference between a theta join, equijoin and natural join
...ed SQL query would be like this (you can play with all the examples here)
SELECT *
FROM Product
JOIN Component
ON Product.Pname = Component.Pname
and the result:
| PNAME | PRICE | CNAME | COST |
----------------------------------
| Laptop | 1500 | CPU | 500 |
| Laptop | 1500 | hdd ...
MySQL error: key specification without a key length
...d, and the trick is to choose a number N that’s long enough to give good selectivity, but short enough to save space. The prefix should be long enough to make the index nearly as useful as it would be if you’d indexed the whole column.
Before we go further let us define some important terms. In...
T-SQL stored procedure that accepts multiple Id values
...nguages only.
XML. Very good for inserting many rows; may be overkill for SELECTs.
Table of Numbers. Higher performance/complexity than simple iterative method.
Fixed-length Elements. Fixed length improves speed over the delimited string
Function of Numbers. Variations of Table of Numbers and fixed...
Is the LIKE operator case-sensitive with MSSQL Server?
...en-us/library/ms144250(v=sql.105).aspx
(a) To check a instance collation
select serverproperty('collation')
(b) To check a database collation
select databasepropertyex('databasename', 'collation') sqlcollation
(c) To create a database using a different collation
create database exampledataba...
Random row selection in Pandas dataframe
Is there a way to select random rows from a DataFrame in Pandas.
6 Answers
6
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What does SQL clause “GROUP BY 1” mean?
...
SELECT account_id, open_emp_id
^^^^ ^^^^
1 2
FROM account
GROUP BY 1;
In above query GROUP BY 1 refers to the first column in select statement which is
account_id.
You also can speci...
How do you count the number of occurrences of a certain substring in a SQL varchar?
...mparing the lengths
Declare @string varchar(1000)
Set @string = 'a,b,c,d'
select len(@string) - len(replace(@string, ',', ''))
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- how to allow only one item selected?
I have a <SELECT multiple> field with multiple options and I want to allow it to have only one option selected at the same time but user can hold CTRL key and select more items at once.
...