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Turning a Comma Separated string into individual rows
I have a SQL Table like this:
16 Answers
16
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How do I use ROW_NUMBER()?
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For the first question, why not just use?
SELECT COUNT(*) FROM myTable
to get the count.
And for the second question, the primary key of the row is what should be used to identify a particular row. Don't try and use the row number for that.
If you returned Row_Number() in your main...
OPTION (RECOMPILE) is Always Faster; Why?
...You hit the nail on the head when you mentioned a query initially run on a table with 10 records, and now the table has millions of records. That was my case exactly. I didn't mention it in the post because I didn't think it mattered. Fascinating stuff. Thanks again.
– Chad Dec...
Postgres: clear entire database before re-creating / re-populating from bash script
...g_dump and pg_restore directly together over a pipe.
To drop and recreate tables, you could use the --clean command-line option for pg_dump to emit SQL commands to clean (drop) database objects prior to (the commands for) creating them. (This will not drop the whole database, just each table/sequen...
How can I get enum possible values in a MySQL database?
...ou. It also strips the quotes from the values.
function get_enum_values( $table, $field )
{
$type = $this->db->query( "SHOW COLUMNS FROM {$table} WHERE Field = '{$field}'" )->row( 0 )->Type;
preg_match("/^enum\(\'(.*)\'\)$/", $type, $matches);
$enum = explode("','", $matches...
Storing time-series data, relational or non?
... clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a 16 billion row table is instantaneous).
Your table has one serious impediment. Given your description, the actual PK is (Device, Metric, DateTime). (Please don't call it TimeStamp, that mea...
Is a view faster than a simple query?
...y referenced by another query as the optimizer will use them in place of a table reference when appropriate.
Again, the documentation:
The indexed view can be used in a query execution in two ways. The query can reference the indexed view directly, or, more importantly, the query optimizer c...
How to convert a string or integer to binary in Ruby?
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Picking up on bta's lookup table idea, you can create the lookup table with a block. Values get generated when they are first accessed and stored for later:
>> lookup_table = Hash.new { |h, i| h[i] = i.to_s(2) }
=> {}
>> lookup_table[1]...
Why do Lua arrays(tables) start at 1 instead of 0?
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In Programming in Lua's first discussion of tables, they mention:
Since you can index a table with any value, you can start the indices of an array with any number that pleases you. However, it is customary in Lua to start arrays with 1 (and not with 0, as in C) an...
nvarchar(max) vs NText
...ld mean some scary long queries where SQL Server would have to rebuild the table and copy everything over, bringing down my websites and raising my heartrate.
I was also concerned that the Linq2SQL could cause errors if it was doing some kind of verification of the column type.
Happy to report tho...