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Filter rows which contain a certain string
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head
#> # A tibble: 6 x 10
#> carat cut color clarity depth table price x y z
#> <dbl> <ord> <ord> <ord> <dbl> <dbl> <int> <dbl> <dbl> <dbl>
#> 1 0.23 Ideal E SI2 61.5 55 326 3.95 3....
How are virtual functions and vtable implemented?
...ons in C++":
Whenever a program has a virtual function declared, a v - table is constructed for the class. The v-table consists of addresses to the virtual functions for classes that contain one or more virtual functions. The object of the class containing the virtual function contains a virtual...
MySQL Multiple Joins in one query?
...ally works? Is the second join joining the results of the first join with table 3, or is it joining table 1 with table 3 separately? (i.e., joining table 1 with table 2, and then joining table 1 separately with table 3, then returning it all back?) Does that make sense? I ask because I've been do...
MYSQL Truncated incorrect DOUBLE value
...se I was not using apostrophes in where clause.
Like my query was
update table set coulmn1='something' where column2 in (00012121);
when I changed where clause to where column2 in ('00012121'); then the query worked fine for me.
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How to join (merge) data frames (inner, outer, left, right)
...f performance is a major issue for you, you should also look into the data.table package - that's a whole new set of join syntax, but it's radically faster than anything we're talking about here.
– Matt Parker
Feb 12 '13 at 16:22
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Rename column SQL Server 2008
I am using SQL Server 2008 and Navicat. I need to rename a column in a table using SQL.
11 Answers
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Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
I have the following table:
4 Answers
4
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Changing the size of a column referenced by a schema-bound view in SQL Server
...SDN:
SCHEMABINDING
Binds the view to the schema of the underlying table or tables. When
SCHEMABINDING is specified, the base
table or tables cannot be modified in
a way that would affect the view
definition. The view definition itself
must first be modified or dropped to
remove ...
Copy values from one column to another in the same table
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Short answer for the code in question is:
UPDATE `table` SET test=number
Here table is the table name and it's surrounded by grave accent (aka back-ticks `) as this is MySQL convention to escape keywords (and TABLE is a keyword in that case).
BEWARE, that this is pretty d...
Disable Laravel's Eloquent timestamps
... we don't want to add the updated_at / created_at fields to all of our tables as we have a logging class that does all this in more depth for us already.
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