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How to select distinct rows in a datatable and store into an array
I have a dataset objds. objds contains a table named Table1. Table1 contains column named ProcessName. This ProcessName contains repeated names.So i want to select only distinct names.Is this possible.
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Are PDO prepared statements sufficient to prevent SQL injection?
...ght get to see someone else's password. Since the first few names in users table tend to be admins, you may have also just given away the farm. (Also note: this is one more reason not to store passwords in plain text!)
We see, then, that prepared statements are enough for a single query, but by the...
JPA or JDBC, how are they different?
...I used EntityManager and with the get methods could access the stored data table.
4 Answers
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Getting the minimum of two values in SQL
... Then @PaidThisMonth Else @OwedPast End PaidForPast
As Inline table valued UDF
CREATE FUNCTION Minimum
(@Param1 Integer, @Param2 Integer)
Returns Table As
Return(Select Case When @Param1 < @Param2
Then @Param1 Else @Param2 End MinValue)
Usage:
Select MinValue ...
Summarizing multiple columns with dplyr? [duplicate]
... 2.87
#> 3 3 2.85 2.95 2.95 3.06
Also don't forget about data.table (use keyby to sort sort groups):
library(data.table)
setDT(df)[, lapply(.SD, mean), keyby = grp]
#> grp a b c d
#> 1: 1 3.079412 2.979412 2.979412 2.914706
#> 2: 2 3.029126 3....
Cleanest way to build an SQL string in Java
...pared statements:
PreparedStatement stm = c.prepareStatement("UPDATE user_table SET name=? WHERE id=?");
stm.setString(1, "the name");
stm.setInt(2, 345);
stm.executeUpdate();
The other thing that can be done is to keep all queries in properties file. For example
in a queries.properties file can ...
How do I use LINQ Contains(string[]) instead of Contains(string)
...ids = arrayofuids.Select(id => int.Parse(id)).ToList();
var selected = table.Where(t => uids.Contains(t.uid));
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UITableView didSelectRowAtIndexPath: not being called on first tap
I'm having an issue with UITableView's didSelectRowAtIndexPath .
16 Answers
16
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How to use GROUP BY to concatenate strings in SQL Server?
...5 and later. Original question didn't specify the version in use.]
CREATE TABLE #YourTable ([ID] INT, [Name] CHAR(1), [Value] INT)
INSERT INTO #YourTable ([ID],[Name],[Value]) VALUES (1,'A',4)
INSERT INTO #YourTable ([ID],[Name],[Value]) VALUES (1,'B',8)
INSERT INTO #YourTable ([ID],[Name],[Value]...
NOT IN vs NOT EXISTS
...OT IN sub query were to return no results at all (i.e. the [Order Details] table is empty). In which case it should. In the plan for my sample data this is implemented by adding another anti semi join as below.
The effect of this is shown in the blog post already linked by Buckley. In the example...