CREATE TABLE table_2155836_1 (_per_capita_ VARCHAR2, gdp__ppp___usd NUMBER, country VARCHAR2)

What is the GDP (PPP) (USD, per capita) for Algeria?
SELECT MIN(gdp__ppp___usd), _per_capita_ FROM table_2155836_1 WHERE country = "Algeria"
SELECT MIN("gdp__ppp___usd"), "_per_capita_" FROM "table_2155836_1" WHERE "Algeria" = "country"