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How To Create Table with Identity Column
I have an existing table that I am about to blow away because I did not create it with the ID column set to be the table's Identity column.
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Adding 'serial' to existing column in Postgres
I have a small table (~30 rows) in my Postgres 9.0 database with an integer ID field (the primary key) which currently contains unique sequential integers starting at 1, but which was not created using the 'serial' keyword.
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Add column to SQL Server
I need to add a column to my SQL Server table. Is it possible to do so without losing the data, I already have?
5 Answers...
INSERT INTO…SELECT for all MySQL columns
...The correct syntax is described in the manual. Try this:
INSERT INTO this_table_archive (col1, col2, ..., coln)
SELECT col1, col2, ..., coln
FROM this_table
WHERE entry_date < '2011-01-01 00:00:00';
If the id columns is an auto-increment column and you already have some data in both tables the...
MySQL select 10 random rows from 600K rows fast
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SELECT column FROM table
ORDER BY RAND()
LIMIT 10
Not the efficient solution but works
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Oracle “(+)” Operator
..., because the ANSI-89 format (using a comma in the FROM clause to separate table references) didn't standardize OUTER joins.
The query would be re-written in ANSI-92 syntax as:
SELECT ...
FROM a
LEFT JOIN b ON b.id = a.id
This link is pretty good at explaining the difference between JOIN...
How to list records with date from the last 10 days?
...hy don't you just try it?
The standard ANSI SQL format would be:
SELECT Table.date
FROM Table
WHERE date > current_date - interval '10' day;
I prefer that format as it makes things easier to read (but it is the same as current_date - 10).
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How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...ions:
Individual insert/update operations in a retry loop; or
Locking the table and doing batch merge
Individual row retry loop
Using individual row upserts in a retry loop is the reasonable option if you want many connections concurrently trying to perform inserts.
The PostgreSQL documentation co...
What's the best practice for primary keys in tables?
When designing tables, I've developed a habit of having one column that is unique and that I make the primary key. This is achieved in three ways depending on requirements:
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vertical align middle in
...s, so in that case you can wrap your text using span and than use display: table-cell; and display: table; along with vertical-align: middle;, also don't forget to use width: 100%; for #abc
Demo
#abc{
font:Verdana, Geneva, sans-serif;
font-size:18px;
text-align:left;
background-color:#0F0;...