Spark SQL 指南

OFFSET 子句

說明

OFFSET 子句用於指定在開始傳回 SELECT 陳述式傳回的列之前要略過的列數。一般來說，此子句與 ORDER BY 連用，以確保結果具有決定性。

語法

OFFSET integer_expression

參數

範例

CREATE TABLE person (name STRING, age INT);
INSERT INTO person VALUES
    ('Zen Hui', 25),
    ('Anil B', 18),
    ('Shone S', 16),
    ('Mike A', 25),
    ('John A', 18),
    ('Jack N', 16);

-- Skip the first two rows.
SELECT name, age FROM person ORDER BY name OFFSET 2;
+-------+---+
|   name|age|
+-------+---+
| John A| 18|
| Mike A| 25|
|Shone S| 16|
|Zen Hui| 25|
+-------+---+

-- Skip the first two rows and returns the next three rows.
SELECT name, age FROM person ORDER BY name LIMIT 3 OFFSET 2;
+-------+---+
|   name|age|
+-------+---+
| John A| 18|
| Mike A| 25|
|Shone S| 16|
+-------+---+

-- A function expression as an input to OFFSET.
SELECT name, age FROM person ORDER BY name OFFSET length('SPARK');
+-------+---+
|   name|age|
+-------+---+
|Zen Hui| 25|
+-------+---+

-- A non-foldable expression as an input to OFFSET is not allowed.
SELECT name, age FROM person ORDER BY name OFFSET length(name);
org.apache.spark.sql.AnalysisException: The offset expression must evaluate to a constant value ...