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11.你用什么方法检查PHP脚本的执行效率(通常是脚本执行时间)和数据库SQL的效率(通常是数据库Query时间),并定位和分析脚本执行和数据库查询的瓶颈所在? 1.脚本执行时间,启用xdebug,使用WinCacheGrind分析。 2.数据库查询,mysql使用EXPLAIN分析查询,启用slow query log记录慢查询。 PHP LAMP Engineer Test Paper Question 1 What does echo count ("123") ?> print out? A) 3 B) False C) Null D) 1 E) 0 Question 2 Which of the following snippets prints a representation of 42 with two decimal places? A) printf("%.2dn", 42); B) printf("%1.2fn", 42); C) printf("%1.2un", 42); Question 3 Given $text = 'Content-Type: text/xml'; Which of the following prints 'text/xml'? A) print substr($text, strchr($text, ':')); B) print substr($text, strchr($text, ':') + 1); C) print substr($text, strpos($text, ':') + 1); D) print substr($text, strpos($text, ':') + 2); E) print substr($text, 0, strchr($text, ':') Question 4 What is the value of $a?
A) True B) False Question 5 What is the value of $result in the following PHP code?
Answer: NULL Question 6 The code below ___________ because ____________.
A) will work, class definitions can be split up into multiple PHP blocks. B) will not work, class definitions must be in a single PHP block. C) will not work, class definitions must be in a single file but can be in multiple PHP blocks. D) will work, class definitions can be split up into multiple files and multiple PHP blocks. Question 7 When turned on, ____________ will _________ your script with different variables from HTML forms and cookies. A) show_errors, enable B) show_errors, show C) register_globals, enhance D) register_globals, inject Question 8 What will be the output of the following PHP code:
Answer: 1 Question 9 What is the best all-purpose way of comparing two strings? A) Using the strpos function B) Using the == operator C) Using strcasecmp() D) Using strcmp() Question 10 What is the difference between "print()" and "echo()"? Answer: print is a function,echo is a language construct |