我有一个带有正则表达式的表,我需要用它来过滤来自另一个表的行.
就像是:
SELECT *
FROM a
WHERE foo SIMILAR TO '(SELECT regex FROM b)'
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显然,这不起作用,因为那不是语法,并且b我需要迭代多行.
我正在使用PostgreSQL 8.3.
我正在尝试使用镶木地板的最小/最大指数.我在这里跟随问题/答案:Spark Parquet Statistics(最小/最大)集成
scala> val foo = spark.sql("select id, cast(id as string) text from range(1000)").sort("id")
scala> foo.printSchema
root
|-- id: long (nullable = false)
|-- text: string (nullable = false)
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当我看一个单独的镶木地板文件时,我没有看到任何最小/最大
> parquet-tools meta part-00000-tid-5174196010762120422-9
5fb2e22-0dfb-4597-bdca-4fb573873959-0-c000.gz.parquet
file: file:.../part-00000-tid-5174196010762120422-95fb2e22-0dfb-4597-bdca-4fb573873959-0-c000.gz.parquet
creator: parquet-mr version 1.8.1 (build 4aba4dae7bb0d4edbcf7923ae1339f28fd3f7fcf)
extra: org.apache.spark.sql.parquet.row.metadata = {"type":"struct","fields":[{"name":"id","type":"long","nullable":false,"metadata":{}},{"name":"text","type":"string","nullable":false,"metadata":{}}]}
file schema: spark_schema
--------------------------------------------------------------------------------
id: REQUIRED INT64 R:0 D:0
text: REQUIRED BINARY O:UTF8 R:0 D:0
row group 1: RC:125 TS:1840 OFFSET:4
--------------------------------------------------------------------------------
id: INT64 GZIP DO:0 FPO:4 SZ:259/1044/4.03 VC:125 ENC:PLAIN,BIT_PACKED
text: …Run Code Online (Sandbox Code Playgroud)