ELT()¶

The ELT() function returns the N-th string argument, counting from 1.

Description¶

The ELT() function returns the N-th string argument, counting from 1. ELT(1, str1, str2, ...) returns str1, ELT(2, ...) returns str2, and so on.

The function returns NULL in any of the following cases:

N is NULL or any of the string arguments evaluated at that index is NULL.
N < 1 or N is greater than the number of string arguments supplied.
N is an integer type (UINT64, BIT) whose value falls outside the valid range.

At least two arguments are required (the index and one string); otherwise, the call is rejected at bind time. Non-string rest arguments are cast to VARCHAR. When any rest argument is BINARY / VARBINARY / BLOB, the result type is BLOB; otherwise, it is VARCHAR.

Syntax¶

> ELT(N, str1, str2, str3, ...)

Arguments¶

Arguments	Description
N	Required. An integer expression selecting which string to return. Types `BOOL`, `INT`, `FLOAT`, and `DECIMAL` are cast to `INT64`; `UINT64` / `BIT` are used as-is.
str1, str2, …	Required. One or more string expressions. Non-string types are cast to `VARCHAR`.

Examples¶

DROP DATABASE IF EXISTS elt_demo;
CREATE DATABASE elt_demo;
USE elt_demo;

SELECT ELT(1, 'Aa', 'Bb', 'Cc', 'Dd') AS r1;
SELECT ELT(3, 'Aa', 'Bb', 'Cc', 'Dd') AS r2;
SELECT ELT(0, 'Aa', 'Bb', 'Cc', 'Dd') AS out_of_range;
SELECT ELT(5, 'Aa', 'Bb', 'Cc', 'Dd') AS out_of_range2;
SELECT ELT(NULL, 'Aa', 'Bb')          AS n_is_null;

DROP DATABASE elt_demo;