1.6 KiB
EVAL [esql-eval]
The EVAL processing command enables you to append new columns with calculated
values.
Syntax
EVAL [column1 =] value1[, ..., [columnN =] valueN]
Parameters
columnX- The column name. If a column with the same name already exists, the existing column is dropped. If a column name is used more than once, only the rightmost duplicate creates a column.
valueX- The value for the column. Can be a literal, an expression, or a function. Can use columns defined left of this one.
Description
The EVAL processing command enables you to append new columns with calculated
values. EVAL supports various functions for calculating values. Refer to
Functions for more information.
Examples
:::{include} ../examples/eval.csv-spec/eval.md :::
If the specified column already exists, the existing column will be dropped, and the new column will be appended to the table:
:::{include} ../examples/eval.csv-spec/evalReplace.md :::
Specifying the output column name is optional. If not specified, the new column
name is equal to the expression. The following query adds a column named
height*3.281:
:::{include} ../examples/eval.csv-spec/evalUnnamedColumn.md :::
Because this name contains special characters, it needs to be quoted with backticks (```) when using it in subsequent commands:
:::{include} ../examples/eval.csv-spec/evalUnnamedColumnStats.md :::