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MySQL stored procedure vs function, which would I use when?
...d procedures with ordinary SQL, whilst with stored function you can.
e.g. SELECT get_foo(myColumn) FROM mytable is not valid if get_foo() is a procedure, but you can do that if get_foo() is a function. The price is that functions have more limitations than a procedure.
...
Select by partial string from a pandas DataFrame
...ns of which 2 contain string values. I was wondering if there was a way to select rows based on a partial string match against a particular column?
...
Is there any JSON Web Token (JWT) example in C#?
...gnedTokens = true,
IssuerSigningKeys = certificates.Values.Select(x => new X509SecurityKey(x)),
IssuerSigningKeyResolver = (token, securityToken, kid, validationParameters) =>
{
return certificates
.Where(x...
Delete duplicate records in SQL Server?
...r the dupes by empId, and delete all but the first one.
delete x from (
select *, rn=row_number() over (partition by EmployeeName order by empId)
from Employee
) x
where rn > 1;
Run it as a select to see what would be deleted:
select *
from (
select *, rn=row_number() over (partition b...
How do I remove the first characters of a specific column in a table?
...
SELECT RIGHT(MyColumn, LEN(MyColumn) - 4) AS MyTrimmedColumn
Edit:
To explain, RIGHT takes 2 arguments - the string (or column) to operate on, and the number of characters to return (starting at the "right" side of the stri...
Splitting string into multiple rows in Oracle
... be an improved way (also with regexp and connect by):
with temp as
(
select 108 Name, 'test' Project, 'Err1, Err2, Err3' Error from dual
union all
select 109, 'test2', 'Err1' from dual
)
select distinct
t.name, t.project,
trim(regexp_substr(t.error, '[^,]+', 1, levels.column_value...
Find a value anywhere in a database
...OT NULL
BEGIN
SET @ColumnName = ''
SET @TableName =
(
SELECT MIN(QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME))
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'
AND QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME) &...
Which MySQL data type to use for storing boolean values
...
When I do a select from the standard mysql command line client bit fields shows up completely blank. Because of this I prefer TINYINT(1).
– User
Nov 2 '12 at 0:53
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Can I concatenate multiple MySQL rows into one field?
...
You can use GROUP_CONCAT:
SELECT person_id, GROUP_CONCAT(hobbies SEPARATOR ', ')
FROM peoples_hobbies
GROUP BY person_id;
As Ludwig stated in his comment, you can add the DISTINCT operator to avoid duplicates:
SELECT person_id, GROUP_CONCAT(DISTINCT ...
SQL SELECT WHERE field contains words
I need a select which would return results like this:
15 Answers
15
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