大约有 43,000 项符合查询结果（耗时：0.0247秒） [XML]
How do I match any character across multiple lines in a regular expression?
...o_mod_m (source).
As for oracle (it is POSIX based), use n option (demo): select regexp_substr('abcde' || chr(10) ||' fghij<Foobar>', '(.*)<Foobar>', 1, 1, 'n', 1) as results from dual
POSIX-based engines:
A mere . already matches line breaks, no need to use any modifiers, see bas...
How to move the cursor word by word in the OS X Terminal
...e sequences for you:
Open Terminal preferences (cmd+,);
At Settings tab, select Keyboard and double-click ⌥ ← if it's there, or add it if it's not.
Set the modifier as desired, and type the shortcut key in the box: esc+B, generating the text \033b (you can't type this text manually).
Repeat fo...
How to export data as CSV format from SQL Server using sqlcmd?
...
You can run something like this:
sqlcmd -S MyServer -d myDB -E -Q "select col1, col2, col3 from SomeTable"
-o "MyData.csv" -h-1 -s"," -w 700
-h-1 removes column name headers from the result
-s"," sets the column seperator to ,
-w 700 sets the row width to 700 chars (this will nee...
How to convert std::string to lower case?
...y unrelated) definition of tolower which would end up being preferentially selected without the ::.
– Charles Ofria
Jul 30 '16 at 16:43
|
sh...
Modify table: How to change 'Allow Nulls' attribute from not null to allow null
...
I wrote this so I could edit all tables and columns to null at once:
select
case
when sc.max_length = '-1' and st.name in ('char','decimal','nvarchar','varchar')
then
'alter table [' + so.name + '] alter column [' + sc.name + '] ' + st.name + '(MAX) NULL'
when st.name in ('char','decimal','n...
Binary Data in MySQL [closed]
... mysql_connect("localhost", "root", "password");
mysql_select_db("binary_data");
$data = mysql_real_escape_string(fread(fopen($form_data, "r"), filesize($form_data)));
$result = mysql_query("INSERT INTO binary_data (description, bin_data, filenam...
SQL Server indexes - ascending or descending, what difference does it make?
...TE INDEX ix_index ON mytable (col1, col2 DESC);
can be used for either:
SELECT *
FROM mytable
ORDER BY
col1, col2 DESC
or:
SELECT *
FROM mytable
ORDER BY
col1 DESC, col2
, but not for:
SELECT *
FROM mytable
ORDER BY
col1, col2
An index on a single colum...
How to color System.out.println output? [duplicate]
...7 | white |
| 39 | 49 | default |
+~~~~~~+~~~~~~+~~~~~~~~~~~+
Select Graphic Rendition (SGR)
SGR just allows you to change the text. Many of these do not work in certain terminals, so use these sparingly in production-level projects. However, they can be useful for making program outpu...
Importance of varchar length in MySQL table
...
Anytime your select query uses a temporary table (group and order by operations, among other things) it will convert varchar(200) to a char(200) and performance will suffer.
– Jamie
Feb 7 '13 at 20:1...
How to use NULL or empty string in SQL
...
Select *
From Table
Where (col is null or col = '')
Or
Select *
From Table
Where IsNull(col, '') = ''
share
|
improve t...