Carsten's Random Ramblings » MySQL Function of the day

DATABASE() :: MySQL Function of the Day

Carsten — Tue, 29 Apr 2008 07:24:42 +0000

Function name: DATABASE() Aliases: - Function type: Information function Purpose: Return the name of the current database Description: DATABASE() returns the value of the currently selected database (default database selected either when logging into the server or through USE database_name). If no database is currently selected as default, DATABASE() returns NULL. $ mysql Welcome to the MySQL monitor. Commands [...]

MySQL Function of the Day: Week Seven

Carsten — Mon, 28 Apr 2008 21:28:46 +0000

The weekly run-down of MFotD

(See this post for background information on MySQL Function of the Day)

Week Seven:

Monday, April 21st, 2008: ROUND()
Tuesday, April 22nd, 2008: TRUNCATE
Wednesday, April 23rd, 2008: LOG()

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ENCODE() :: MySQL Function of the Day

Carsten — Mon, 28 Apr 2008 19:27:25 +0000

Function name: ENCODE Aliases: - Function type: Encryption function Purpose: Encrypt a string using a password Description: ENCODE(’bitbybit.dk’, ‘bIgS3cR3t’) returns “bIQu/AJkKCHU2″, which is the encryption of the string ‘bitbybit’ using the password ‘bIgS3cR3t’. To decrypt the string, use DECODE: mysql> select DECODE('bIQu/AJkKCHU2', 'bIgS3cR3t'); +---------------------------------------------------+ | DECODE('bIQu/AJkKCHU2', 'bIgS3cR3t') | +---------------------------------------------------+ | bitbybit.dk | +---------------------------------------------------+ 1 row in set (0.00 sec) If you copy-pasted any of the above, it [...]

LOG() :: MySQL Function of the Day

Carsten — Wed, 23 Apr 2008 07:51:09 +0000

Function name: LOG() Aliases: (LN, LOG2, LOG10) Function type: Numerical function Purpose: Return the logarithm of a number Description: LOG(x) returns the natural logarithm of x. LOG(y, x) returns the logarithm of x for base y. So LOG(8) returns 2.079, and LOG(2, 8 ) returns 3. Both arguments may be any integer, decimal or floating-point number greater than [...]

TRUNCATE :: MySQL Function of the Day

Carsten — Tue, 22 Apr 2008 07:04:08 +0000

Function name: TRUNCATE Aliases: - Function type: Numerical function Purpose: Round a number toward zero Description: TRUNCATE() works almost, but not quite, like ROUND(), which was discussed yesterday. Firstly, the second parameter is never optional. Secondly, TRUNCATE() always rounds toward 0 and does so by chopping off decimals, without consideration as to what constitutes the “nearest” rounded [...]

ROUND() :: MySQL Function of the Day

Carsten — Mon, 21 Apr 2008 12:27:43 +0000

Function name: ROUND
Aliases: -
Function type: Numerical function
Purpose: Round a number to a certain number of decimal places

Description: MySQLs ROUND() is an extremely versatile implementation of rounding functions wrapped into one single function. To wit:

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MySQL Function of the Day: Week Six

Carsten — Mon, 21 Apr 2008 10:14:32 +0000

The weekly run-down of MFotD

(See this post for background information on MySQL Function of the Day)

Week Six:

Monday, April 14th 2008:REVERSE()
Tuesday, April 15th 2008: CEILING()
Wednesday, April 16 2008: BENCHMARK()
Thursday, April 17 2008: MD5()
Friday, April 18 2008: CRC32()

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CRC32 :: MySQL Function of the Day

Carsten — Fri, 18 Apr 2008 08:03:23 +0000

Function name: CRC32 Aliases: - Function type: Numerical function Purpose: Return a Cyclic Redundancy Check value of a string Description: CRC32() computes a “cyclic redundancy check” value of the input string. It may be used in many of the same places as MD5() (which we discussed yesterday). Historically, CRC has been used to detect noise in transmission signals, [...]

MD5() :: MySQL Function of the Day

Carsten — Thu, 17 Apr 2008 08:02:35 +0000

Function name: MD5() Aliases: - Function type: Encryption/compression function Purpose: Return the MD5 Message-Digest of a string Description: MD5() returns a 128-bit (encoded as 32 hex characters) value with a checksum for a string of arbitrary length: MD5(’bitbybit’): 1e8ef91030bafc87a6491dd641c859ab MD5(’bitBybit’): a6236c6a6a7cff46e9e5f5f18acc1472 This algorithm is often used to produce checksums for both large and small pieces of data, since it’s very hard [...]

BENCHMARK() :: MySQL Function of the Day

Carsten — Wed, 16 Apr 2008 08:06:53 +0000

unction name: BENCHMARK() Aliases: - Function type: Information Function Purpose: Repeat an operation a number of times Description: BENCHMARK(multiplier, operation) executes operation multiplier times: mysql> select BENCHMARK(100000, MD5(’bitbybit’)); +————————————+ | benchmark(100000, md5(’bitbybit’)) | +————————————+ | [...]