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To concatenate more than two strings, nest consecutive CONCAT functions as shown in the example below. Returns the number of characters in string.

You can substitute a field name or another function for these arguments.

For example, FLOOR(POWER(SAMP_ERR, 0.5)) returns the largest integer that is less than or equal to the square root of SAMP_ERR.įor illustrative purposes, the examples in the description column of the following tables mostly use literal arguments. A function that returns a value of the proper type (string, number, or date).If your organization allows nonstandard SQL queries, non-English characters in a string literal must be escaped with N (for example, N'针叶林').A literal, such as 'Sailboat' (a string surrounded by single quotation marks), the number 5, or a date in MM/DD/YYYY hh:mm:ss format, surrounded by single quotation marks.A field name, as long as the field type matches the argument type (string, number, or date).In the tables below, any argument can be as follows: The expression would be TOTALPOP / NULLIF(POP18, 0).įunctions take arguments. You can guard against this using the NULLIF function described below. If any feature has a POP18 equal to zero, the calculation will result in a divide-by-zero error. For example, suppose you need to calculate a double field to be TOTALPOP divided by POP18. Functions work with field names, literals, and other functions. In addition to simple expressions using operators, you can also use functions. If you click a field name in the Fields list, the field is added to the expression.If you hover over a field name in the Fields list, the field alias and field type are displayed.You can filter this list by the field types String, Numeric, and Date. The Fields list shows you all the field names available for calculations. Calculate Field works only with field names, not field aliases.If you have a filter on your layer, only the records that meet the filter criteria.The following are additional considerations: If there are any errors, an error message will appear at the bottom of the dialog box. Do not use a double quotation mark.Īfter you've created your expression, click the Calculate button. To include an apostrophe in the string, use two single quotation marks for the apostrophe.See Numeric functions below for information on the CAST function. For example, if you're calculating a double field named POP to an integer field named SAMPLE, the expression will appear as CAST(SAMPLE AS FLOAT). If you are calculating a field of type double to field of type integer, the CAST function may be automatically added to your expression.You'll need to use the string functions described in the String functions section.