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How to get the mysql table columns data type?
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You can use the information_schema columns table:
SELECT DATA_TYPE FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_name = 'tbl_name' AND COLUMN_NAME = 'col_name';
share
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im...
Join vs. sub-query
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@JinghuiNiu Customers who bought expensive items: select custid from cust join bought using (custid) where price > 500. If a customer bought multiple expensive items, you'll get double-ups. To fix this, select custid from cust where exists (select * from bought where cust...
What are the most useful Intellij IDEA keyboard shortcuts? [closed]
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These are some of my most used keyboard short cuts
Syntax aware selection in the editor selects a word at the caret and then selects expanding areas of the source code. For example, it may select a method name, then the expression that calls this method, then the whole statement, then the...
querySelector and querySelectorAll vs getElementsByClassName and getElementById in JavaScript
I would like to know what exactly is the difference between querySelector and querySelectorAll against getElementsByClassName and getElementById ?
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Join between tables in two different databases?
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Yes, assuming the account has appropriate permissions you can use:
SELECT <...>
FROM A.table1 t1 JOIN B.table2 t2 ON t2.column2 = t1.column1;
You just need to prefix the table reference with the name of the database it resides in.
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Test for non-zero length string in Bash: [ -n “$var” ] or [ “$var” ]
...| true true true true false false| true true true true false false
char | true true true true false false| true true true true false false
hyphn| true true true true false false| true true true true false false
two | -err- true -err- true -err- false| true true true tru...
How can I get the behavior of GNU's readlink -f on a Mac?
...es, sys
libc = ctypes.CDLL('libc.dylib')
libc.realpath.restype = ctypes.c_char_p
libc.__error.restype = ctypes.POINTER(ctypes.c_int)
libc.strerror.restype = ctypes.c_char_p
def realpath(path):
buffer = ctypes.create_string_buffer(1024) # PATH_MAX
if libc.realpath(path, buffer):
ret...
Should you choose the MONEY or DECIMAL(x,y) datatypes in SQL Server?
...@num2 DECIMAL(19,4),
@num3 DECIMAL(19,4),
@num4 DECIMAL(19,4)
SELECT
@mon1 = 100, @mon2 = 339, @mon3 = 10000,
@num1 = 100, @num2 = 339, @num3 = 10000
SET @mon4 = @mon1/@mon2*@mon3
SET @num4 = @num1/@num2*@num3
SELECT @mon4 AS moneyresult,
@num4 AS numericresult...
using facebook sdk in Android studio
... what you want).
Open project structure by Ctrl + Shift + Alt + S and then select dependencies tab. Click on + button and select Module Dependency. In the new window pop up select :facebook.
You should be good to go.
Instructions for older Android Studio and older Facebook SDK
This applies to A...
- how to allow only one item selected?
I have a <SELECT multiple> field with multiple options and I want to allow it to have only one option selected at the same time but user can hold CTRL key and select more items at once.
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