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How to see indexes for a database or table in MySQL?
...pecific schema you can use the STATISTICS table from INFORMATION_SCHEMA:
SELECT DISTINCT
TABLE_NAME,
INDEX_NAME
FROM INFORMATION_SCHEMA.STATISTICS
WHERE TABLE_SCHEMA = 'your_schema';
Removing the where clause will show you all indexes in all schemas.
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IN clause and placeholders
...mes = { "name1", "name2" }; // do whatever is needed first
String query = "SELECT * FROM table"
+ " WHERE name IN (" + makePlaceholders(names.length) + ")";
Cursor cursor = mDb.rawQuery(query, names);
Just make sure to pass exactly as many values as places. The default maximum limit of host pa...
Drop data frame columns by name
...op=FALSE to keep R from converting your data frame to a vector if you only select a single column. Don't forget that data frames are lists, so list selection (one-dimensional like I did) works perfectly well and always returns a list. Or a data frame in this case, which is why I prefer to use it.
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“where 1=1” statement [duplicate]
...hould ignore it
No magic, just practical
Example Code:
commandText = "select * from car_table where 1=1";
if (modelYear <> 0) commandText += " and year="+modelYear
if (manufacturer <> "") commandText += " and value="+QuotedStr(manufacturer)
if (color <> "") command...
Extract a dplyr tbl column as a vector
...2 3.62 3.54 4.11
A nice way to do this in v0.2 of dplyr:
iris2 %>% select(Species) %>% collect %>% .[[5]]
Or if you prefer:
iris2 %>% select(Species) %>% collect %>% .[["Species"]]
Or if your table isn't too big, simply...
iris2 %>% collect %>% .[["Species"]]
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How to set caret(cursor) position in contenteditable element (div)?
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In most browsers, you need the Range and Selection objects. You specify each of the selection boundaries as a node and an offset within that node. For example, to set the caret to the fifth character of the second line of text, you'd do the following:
function s...
Locate current file in IntelliJ
...ecause you followed a reference to java.io.File.
The keymap defines it as Select current file or symbol in any view.
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How to get an object's property's value by property name?
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Sure
write-host ($obj | Select -ExpandProperty "SomeProp")
Or for that matter:
$obj."SomeProp"
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MySQL Results as comma separated list
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You can use GROUP_CONCAT to perform that, e.g. something like
SELECT p.id, p.name, GROUP_CONCAT(s.name) AS site_list
FROM sites s
INNER JOIN publications p ON(s.id = p.site_id)
GROUP BY p.id, p.name;
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Eclipse: How do you change the highlight color of the currently selected method/expression?
...from the Annotation types list.
Then, be sure that Text as highlighted is selected, then choose the desired color.
And, a picture is worth a thousand words...
(source: coobird.net)
(source: coobird.net)
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