which compress 是什么意思
时间: 2023-10-17 19:06:12 浏览: 36
"which compress" 可以翻译成“哪种压缩”,其中“which”表示“哪个/哪种”,“compress”表示“压缩”。这个短语通常用于询问对某个文件或数据进行压缩时使用的压缩算法或工具。例如:Which compress algorithm did you use to compress this file?(你用哪种压缩算法压缩了这个文件?)
相关问题
Applying mtd-add-no-compress-files.patch using plaintext: cat: '': No such file or directory patching file jffsX-utils/mkfs.jffs2.c Applying mtd-include-acl.patch using plaintext: cat: '': No such file or directory The next patch would create the file include/acl.h, which already exists! Assume -R? [n]
这是一个关于应用补丁的命令行操作,具体是在对文件系统进行打补丁时出现了一些问题。第一个问题是在应用名为"mtd-add-no-compress-files.patch"的补丁时,出现了文件不存在的错误。第二个问题是在应用名为"mtd-include-acl.patch"的补丁时,出现了文件已存在的警告。针对第二个问题,系统询问是否应该覆盖已存在的文件。你需要根据实际情况进行操作,如果需要覆盖已存在的文件,输入"y",否则输入"n"。
hive io.compression.codecs
Hive `io.compression.codecs` is a configuration property that specifies the list of compression codecs to be used by Hive for compressing and decompressing data. By default, Hive supports the following compression codecs:
- `org.apache.hadoop.io.compress.DefaultCodec`: The default codec for Hadoop, which uses the deflate algorithm for compression.
- `org.apache.hadoop.io.compress.GzipCodec`: The gzip codec for compression.
- `org.apache.hadoop.io.compress.BZip2Codec`: The bzip2 codec for compression.
- `org.apache.hadoop.io.compress.SnappyCodec`: The snappy codec for compression.
- `org.apache.hadoop.io.compress.Lz4Codec`: The lz4 codec for compression.
To specify the compression codecs, you can set the `io.compression.codecs` property in the `hive-site.xml` configuration file:
```
<property>
<name>io.compression.codecs</name>
<value>org.apache.hadoop.io.compress.DefaultCodec,org.apache.hadoop.io.compress.GzipCodec,org.apache.hadoop.io.compress.BZip2Codec,org.apache.hadoop.io.compress.SnappyCodec,org.apache.hadoop.io.compress.Lz4Codec</value>
</property>
```
You can also specify the compression codec for a specific table or partition using the `STORED AS` clause in the `CREATE TABLE` statement:
```
CREATE TABLE my_table (
...
)
PARTITIONED BY (dt string)
STORED AS PARQUET
TBLPROPERTIES ("parquet.compression"="snappy");
```
In this example, the data for the `my_table` table is stored in the Parquet format with the snappy codec for compression.