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Can you create nested WITH clauses for Common Table Expressions?
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While not strictly nested, you can use common table expressions to reuse previous queries in subsequent ones.
To do this, the form of the statement you are looking for would be
WITH x AS
(
SELECT * FROM MyTable
),
y AS
(
SELECT * FROM x
)
SELECT * FROM y
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MySQL OPTIMIZE all tables?
MySQL has an OPTIMIZE TABLE command which can be used to reclaim unused space in a MySQL install. Is there a way (built-in command or common stored procedure) to run this optimization for every table in the database and/or server install, or is this something you'd have to script up yourself?
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PHP: exceptions vs errors?
... ul.code li.line {
color : red;
}
table.trace {
width : 100%;
border-collapse : collapse;
border : solid 1px black;
}
table.thead tr {
background : rgb(240,240,240);
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What's the difference between deque and list STL containers?
..., it is frequently one of the most important reasons to select the most suitable container for a certain application.
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Does order of where clauses matter in SQL?
Let's say I have a table called PEOPLE having 3 columns ID, LastName, FirstName , none of these columns are indexed.
LastName is more unique, and FirstName is less unique.
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What should I name a table that maps two tables together? [closed]
Let's say I have two tables:
24 Answers
24
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SQL select join: is it possible to prefix all columns as 'prefix.*'?
I'm wondering if this is possible in SQL. Say you have two tables A and B, and you do a select on table A and join on table B:
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Handling an empty UITableView. Print a friendly message
I have a UITableView that in some cases it is legal to be empty. So instead of showing the
background image of the app, I would prefer to print a friendly message in the screen, such as:
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How do I get textual contents from BLOB in Oracle SQL
...HAR2) :
select utl_raw.cast_to_varchar2(dbms_lob.substr(BLOB_FIELD)) from TABLE_WITH_BLOB where ID = '<row id>';
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How to add column if not exists on PostgreSQL?
Question is simple. How to add column x to table y , but only when x column doesn't exist ? I found only solution here how to check if column exists.
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