...Hold many different numerical data. You can store integer INT, decimal NUMERIC, and money MONEY. INT VS SMALLINT VS TINYINT The difference is just the character length: The table count of INT type data ranges from -2, 147, 483, 647 to 2, 147, 483, 647. The SMALLINT type data can be stored.
is_numeric: Detect whether it is a numeric string, which can be a negative number and a decimal number ctype_digit: Detect whether the characters in the string are all numbers. Negative numbers and decimal numbers will fail. Note that the parameters must be strings. If they are not strings, they will return 0/FASLE. The following is a test example: ...
...re, Not applicable: Not applicable to detect parameters that can be 0. is_numeric();——It is only suitable for detecting numbers, but if the parameter name does not exist, an error will occur, so it is not suitable for detecting the first layer. Comprehensive example: <?php ini_set("display_errors",1); //ini_set(...
...is ture, not applicable scope: not applicable to detect parameters that can be 0. is_numeric();——It is only suitable for detecting numbers, but if the parameter name does not exist, an error will occur, so it is not suitable for detecting the first layer. Comprehensive example: Copy the code The code is as follows:
...r>echo "0 is null;"; }else{ echo "0 is not null;"; } if(is_numeric($a)){ echo "0 is numeric;"; }else{ echo "0 is not numeric;"; } if(is_string($a))
... Sometimes when you output time, you will report an error: A non well formed numeric value encountered The problem that occurs at this time is likely to be that the data read from the database is incorrect. At this time, as long as you force the data format to convert it, it will be OK. For example, the problem I have encountered:...
decimal(numeric ) is synonymous with precise storage of numbers float and real cannot accurately store numbers decimal The decimal data type can store up to 38 numbers, and all numbers can be placed to the right of the decimal point. The decimal data type stores an accurate (precise) digital expression; not stored near. Define decimal...
...is ture, not applicable scope: not applicable to detect parameters that can be 0. is_numeric();——It is only suitable for detecting numbers, but if the parameter name does not exist, an error will occur, so it is not suitable for detecting the first layer. Comprehensive example: Copy code code such as...
...When an int type number returns 1, otherwise return 0is_numeric: is a number/numeric string (if it is a pure numeric string, it will return false if there are characters), return 1example: is_numeric(1234);//trueis_nu...
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