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How many characters can UTF-8 encode?
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According to this table* UTF-8 should support:
231 = 2,147,483,648 characters
However, RFC 3629 restricted the possible values, so now we're capped at 4 bytes, which gives us
221 = 2,097,152 characters
Note that a good chunk of those chara...
PostgreSQL - fetch the row which has the Max value for a column
I'm dealing with a Postgres table (called "lives") that contains records with columns for time_stamp, usr_id, transaction_id, and lives_remaining. I need a query that will give me the most recent lives_remaining total for each usr_id
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What does the brk() system call do?
...does stuff (after I drew it I discovered that Linux actually puts the executable much closer to address zero than I thought it did, and the shared libraries at surprisingly high addresses). The black regions of this diagram are unmapped -- any access causes an immediate segfault -- and they are giga...
App Inventor Tutorials and Examples: Dynamic Table Layout | Pura Vida Apps
...vacy Policy Contact Dynamic Table Layout and Table Listpicker Thank you Christopher for being the sponsor of the App Inventor 2 version! It was asked in the App Inventor Forum, how to display a table in App Inventor without knowing how m...
org.hibernate.MappingException: Could not determine type for: java.util.List, at table: College, for
I'm using Hibernate for all CRUD operations in my project. It doesn't work for One-To-Many and Many-To-One relationships. It gives me the below error.
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How to do an update + join in PostgreSQL?
...ATE syntax is:
[ WITH [ RECURSIVE ] with_query [, ...] ]
UPDATE [ ONLY ] table [ [ AS ] alias ]
SET { column = { expression | DEFAULT } |
( column [, ...] ) = ( { expression | DEFAULT } [, ...] ) } [, ...]
[ FROM from_list ]
[ WHERE condition | WHERE CURRENT OF cursor_name ]
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How does one reorder columns in a data frame?
...ec]
return(data)
}
Now the OP's request becomes as simple as this:
table <- data.frame(Time=c(1,2), In=c(2,3), Out=c(3,4), Files=c(4,5))
table
## Time In Out Files
##1 1 2 3 4
##2 2 3 4 5
arrange.vars(table, c("Out"=2))
## Time Out In Files
##1 1 3 2 4
##2...
How can I select from list of values in SQL Server
...g them:
[MS official] https://docs.microsoft.com/en-us/sql/t-sql/queries/table-value-constructor-transact-sql
http://www.sql-server-helper.com/sql-server-2008/row-value-constructor-as-derived-table.aspx
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SQL Server query - Selecting COUNT(*) with DISTINCT
In SQL Server 2005 I have a table cm_production that lists all the code that's been put into production. The table has a ticket_number, program_type, and program_name and push_number along with some other columns.
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Regular expression for a string that does not start with a sequence
I'm processing a bunch of tables using this program , but I need to ignore ones that start with the label "tbd_". So far I have something like [^tbd_] but that simply not match those characters.
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