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JOIN queries vs multiple queries

...han several queries? (You run your main query, and then you run many other SELECTs based on the results from your main query) ...
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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) &...
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Select SQL Server database size

... Try this one - Query: SELECT database_name = DB_NAME(database_id) , log_size_mb = CAST(SUM(CASE WHEN type_desc = 'LOG' THEN size END) * 8. / 1024 AS DECIMAL(8,2)) , row_size_mb = CAST(SUM(CASE WHEN type_desc = 'ROWS' THEN size END) ...
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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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Clear form field after select for jQuery UI Autocomplete

I'm developing a form, and using jQuery UI Autocomplete. When the user selects an option, I want the selection to pop into a span appended to the parent <p> tag. Then I want the field to clear rather than be populated with the selection. ...
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Extract date (yyyy/mm/dd) from a timestamp in PostgreSQL

... to a date by suffixing it with ::date. Here, in psql, is a timestamp: # select '2010-01-01 12:00:00'::timestamp; timestamp --------------------- 2010-01-01 12:00:00 Now we'll cast it to a date: wconrad=# select '2010-01-01 12:00:00'::timestamp::date; date ------------ 201...
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Remove Trailing Spaces and Update in Columns in SQL Server

... Try SELECT LTRIM(RTRIM('Amit Tech Corp ')) LTRIM - removes any leading spaces from left side of string RTRIM - removes any spaces from right Ex: update table set CompanyName = LTRIM(RTRIM(CompanyName)) ...
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Difference between two dates in MySQL

... SELECT TIMEDIFF('2007-12-31 10:02:00','2007-12-30 12:01:01'); -- result: 22:00:59, the difference in HH:MM:SS format SELECT TIMESTAMPDIFF(SECOND,'2007-12-30 12:01:01','2007-12-31 10:02:00'); -- result: 79259 the differenc...
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T-SQL get SELECTed value of stored procedure

...UTPUT parameter and a result set ALSO, watch out if you use the pattern: SELECT @Variable=column FROM table ... if there are multiple rows returned from the query, your @Variable will only contain the value from the last row returned by the query. RETURN VALUE since your query returns an int fie...
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How can I confirm a database is Oracle & what version it is using SQL?

I'm building an installer for an application. The user gets to select a datasource they have configured and nominate what type of database it is. I want to confirm that the database type is indeed Oracle, and if possible, what version of Oracle they are running by sending a SQL statement to the dat...