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How to increase scrollback buffer size in tmux?
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I ended up settling on set-option -g history-limit 50000
– phs
Sep 27 '17 at 0:48
2
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Capitalize first letter. MySQL
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It's almost the same, you just have to change to use the CONCAT() function instead of the + operator :
UPDATE tb_Company
SET CompanyIndustry = CONCAT(UCASE(LEFT(CompanyIndustry, 1)),
SUBSTRING(CompanyIndustry, 2));
This would turn hello to Hello, wO...
Merge two (or more) lists into one, in C# .NET
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You can use the LINQ Concat and ToList methods:
var allProducts = productCollection1.Concat(productCollection2)
.Concat(productCollection3)
.ToList();
Note that there are ...
Simulating group_concat MySQL function in Microsoft SQL Server 2005?
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This only shows how to concat values - group_concat concats them by group, which is more challenging (and what the OP appears to require). See the accepted answer to SO 15154644 for how to do this - the WHERE clause is the critical addition
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what is the preferred way to mutate a React state?
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concat returns a new array, so you can do
this.setState({list: this.state.list.concat([newObject])});
another alternative is React's immutability helper
var newState = React.addons.update(this.state, {
list : {
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Include headers when using SELECT INTO OUTFILE?
... how to get column list of table my_table in my_schema.
-- override GROUP_CONCAT limit of 1024 characters to avoid a truncated result
set session group_concat_max_len = 1000000;
select GROUP_CONCAT(CONCAT("'",COLUMN_NAME,"'"))
from INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'my_table'
AND TABLE...
Comparing two dataframes and getting the differences
...to find changes, but symmetric difference. For that, one approach might be concatenate dataframes:
>>> df = pd.concat([df1, df2])
>>> df = df.reset_index(drop=True)
group by
>>> df_gpby = df.groupby(list(df.columns))
get index of unique records
>>> idx = [...
Is there a performance gain in using single quotes vs double quotes in ruby?
... x.report("assign double") { n.times do; c = "a string"; end}
x.report("concat single") { n.times do; 'a string ' + 'b string'; end}
x.report("concat double") { n.times do; "a string " + "b string"; end}
end
$ ruby benchmark_quotes.rb
user system total r...
How to remove all MySQL tables from the command-line without DROP database permissions? [duplicate]
...execute it:
SET FOREIGN_KEY_CHECKS = 0;
SET @tables = NULL;
SELECT GROUP_CONCAT('`', table_schema, '`.`', table_name, '`') INTO @tables
FROM information_schema.tables
WHERE table_schema = 'database_name'; -- specify DB name here.
SET @tables = CONCAT('DROP TABLE ', @tables);
PREPARE stmt FRO...
What is the most efficient way to create a dictionary of two pandas Dataframe columns?
...50,000 rows:
df = pd.DataFrame(np.random.randint(32, 120, 100000).reshape(50000,2),columns=list('AB'))
df['A'] = df['A'].apply(chr)
%timeit dict(zip(df.A,df.B))
%timeit pd.Series(df.A.values,index=df.B).to_dict()
%timeit df.set_index('A').to_dict()['B']
Output:
100 loops, best of 3: 7.04 ms per...
