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MySQL INNER JOIN select only one row from second table
I have a users table and a payments table, for each user, those of which have payments, may have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL sta...
SQL Server Index Naming Conventions [closed]
...dexes
All of my index name take the form of
<index or key type>_<table name>_<column 1>_<column 2>_<column n>
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Change cursor to hand when mouse goes over a row in table
...he cursor pointer to hand when my mouse goes over a <tr> in a <table>
11 Answers
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Python: List vs Dict for look up table
I have about 10million values that I need to put in some type of look up table, so I was wondering which would be more efficient a list or dict ?
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What columns generally make good indexes?
...portant role in query optimization and searching the results speedily from tables. So it is most important step to select which columns to be indexed. There are two major places where we can consider indexing: columns referenced in the WHERE clause and columns used in JOIN clauses. In short, such co...
Simple way to copy or clone a DataRow?
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You can use ImportRow method to copy Row from DataTable to DataTable with the same schema:
var row = SourceTable.Rows[RowNum];
DestinationTable.ImportRow(row);
Update:
With your new Edit, I believe:
var desRow = dataTable.NewRow();
var sourceRow = dataTable.Rows[rowNum]...
How to get a table cell value using jQuery?
I am trying to work out how to get the value of table cell for each row using jQuery.
9 Answers
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What is the difference between Scope_Identity(), Identity(), @@Identity, and Ident_Current()?
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The ident_current(name) returns the last identity created for a specific table or view in any session.
The identity() function is not used to get an identity, it's used to create an identity in a select...into query.
The session is the database connection. The scope is the current query or the c...
Select rows which are not present in other table
I've got two postgresql tables:
4 Answers
4
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How to append rows to an R data frame
...O I come with 4 distinct solutions:
rbindlist to the data.frame
Use data.table's fast set operation and couple it with manually doubling the table when needed.
Use RSQLite and append to the table held in memory.
data.frame's own ability to grow and use custom environment (which has reference seman...