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How important is the order of columns in indexes?
I've heard that you should put columns that will be the most selective at the beginning of the index declaration. Example:
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Search for all occurrences of a string in a mysql database [duplicate]
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In phpMyAdmin a 'Search' feature is available:
Select particular database not table.
Click 'Search' tab
Enter the search term you want
Select the tables you want to search in
phpMyAdmin screen shot:
The 'Search' feature is also available in MySQL Workbench:
Databa...
FIND_IN_SET() vs IN()
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SELECT name
FROM orders,company
WHERE orderID = 1
AND companyID IN (attachedCompanyIDs)
attachedCompanyIDs is a scalar value which is cast into INT (type of companyID).
The cast only returns numbers up to the...
How do I get list of all tables in a database using TSQL?
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SQL Server 2000, 2005, 2008, 2012, 2014, 2016, 2017 or 2019:
SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE='BASE TABLE'
To show only tables from a particular database
SELECT TABLE_NAME
FROM <DATABASE_NAME>.INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE'...
Fix code indentation in Xcode
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Before Xcode 9 (for Xcode 9 see default shortcut below)
select text
right-click
there's a "Re-indent selection" item in popup menu
In XCode 4 there is one more step:
select text
right-click
Click on "Structure"
there's a "Re-indent selection" and other options in popup men...
Find a string by searching all tables in SQL Server Management Studio 2008
...T 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_N...
Case in Select Statement
I have an SQL statement that has a CASE from SELECT and I just can't get it right. Can you guys show me an example of CASE where the cases are the conditions and the results are from the cases. For example:
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Postgres manually alter sequence
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The parentheses are misplaced:
SELECT setval('payments_id_seq', 21, true); # next value will be 22
Otherwise you're calling setval with a single argument, while it requires two or three.
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How do I execute a stored procedure once for each row returned by query?
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declare @field1 int
declare @field2 int
declare cur CURSOR LOCAL for
select field1, field2 from sometable where someotherfield is null
open cur
fetch next from cur into @field1, @field2
while @@FETCH_STATUS = 0 BEGIN
--execute your sproc on each row
exec uspYourSproc @field1, @fiel...
What is the best way to auto-generate INSERT statements for a SQL Server table?
...2008:
Right-click on the database and go to Tasks > Generate Scripts.
Select the tables (or objects) that you want to generate the script against.
Go to Set scripting options tab and click on the Advanced button.
In the General category, go to Type of data to script
There are 3 options: Schema ...