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Generating a random & unique 8 character string using MySQL

...umn: INSERT INTO vehicles VALUES (blah); -- leaving out the number plate SELECT @lid:=LAST_INSERT_ID(); UPDATE vehicles SET numberplate=concat( substring('ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789', rand(@seed:=round(rand(@lid)*4294967296))*36+1, 1), substring('ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789'...
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What is the meaning of the prefix N in T-SQL statements and when should I use it?

...1. It is an Nvarchar This query fails to match Exact Value That Exists. SELECT TOP 1 * FROM myTable1 WHERE MyCol1 = 'ESKİ' // 0 result using prefix N'' fixes it SELECT TOP 1 * FROM myTable1 WHERE MyCol1 = N'ESKİ' // 1 result - found!!!! Why? Because latin1_general doesn't have big...
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Difference between Char.IsDigit() and Char.IsNumber() in C#

What's the difference between Char.IsDigit() and Char.IsNumber() in C#? 3 Answers ...
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How do you make a HTTP request with C++?

...Addr; int lineCount=0; int rowCount=0; struct hostent *host; locale local; char buffer[10000]; int i = 0 ; int nDataLength; string website_HTML; // website url string url = "www.google.com"; //HTTP GET string get_http = "GET / HTTP/1.1\r\nHost: " + url + "\r\nConnection: close\r\n\r\n"; if (...
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How can mixed data types (int, float, char, etc) be stored in an array?

...minated union, aka tagged union. struct { enum { is_int, is_float, is_char } type; union { int ival; float fval; char cval; } val; } my_array[10]; The type member is used to hold the choice of which member of the union is should be used for each array element. ...
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Postgresql SELECT if string contains

...eld of the record. Concatenate using '||' with the literal percent signs: SELECT id FROM TAG_TABLE WHERE 'aaaaaaaa' LIKE '%' || tag_name || '%'; share | improve this answer | ...
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PostgreSQL “DESCRIBE TABLE”

... 'table' or \ds 'sequence' and so on) The SQL standard way, as shown here: select column_name, data_type, character_maximum_length, column_default, is_nullable from INFORMATION_SCHEMA.COLUMNS where table_name = '<name of table>'; It's supported by many db engines. ...
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'const int' vs. 'int const' as function parameters in C++ and C

...nst are identical. With pointer types it becomes more complicated: const char* is a pointer to a constant char char const* is a pointer to a constant char char* const is a constant pointer to a (mutable) char In other words, (1) and (2) are identical. The only way of making the pointer (rather t...
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How to convert ASCII code (0-255) to its corresponding character?

... code (which is an integer from [0, 255] range) to its corresponding ASCII character? 11 Answers ...
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How do I base64 encode (decode) in C?

I have binary data in an unsigned char variable. I need to convert them to PEM base64 in c. I looked in openssl library but i could not find any function. Does any body have any idea? ...