Find and Extract value after specific String from a file using bash shell script?

问题

I have a file which contains below details : file.txt

+----------------------------------------------------+
|                   createtab_stmt                   |
+----------------------------------------------------+
| CREATE EXTERNAL TABLE `dv.par_kst`( |
|   `col1` string,                                   |
|   `col2` string,                                   |
|   `col3` int,                                      |
|   `col4` int,                                      |
|   `col5` string,                                   |
|   `col6` float,                                    |
|   `col7` int,                                      |
|   `col8` string,                                   |
|   `col9` string,                                   |
|   `col10` int,                                     |
|   `col11` int,                                     |
|   `col12` string,                                  |
|   `col13` float,                                   |
|   `col14` string,                                  |
|   `col15` string)                                  |
| PARTITIONED BY (                                   |
|   `part_col1` int,                                 |
|   `part_col2` int)                                 |
| ROW FORMAT SERDE                                   |
|   'org.apache.hadoop.hive.ql.io.parquet.serde.ParquetHiveSerDe'  |
| STORED AS INPUTFORMAT                              |
|   'org.apache.hadoop.hive.ql.io.parquet.MapredParquetInputFormat'  |
| OUTPUTFORMAT                                       |
|   'org.apache.hadoop.hive.ql.io.parquet.MapredParquetOutputFormat' |
| LOCATION                                           |
|   'hdfs://nameservicets1/dv/hdfsdata/par_kst' |
| TBLPROPERTIES (                                    |
|   'spark.sql.create.version'='2.2 or prior',       |
|   'spark.sql.sources.schema.numPartCols'='2',      |
|   'spark.sql.sources.schema.numParts'='1',         |
|   'spark.sql.sources.schema.part.0'='{"type":"struct","fields":[{"name":"col1","type":"string","nullable":true,"metadata":{}},{"name":"col2","type":"string","nullable":true,"metadata":{}},{"name":"col3","type":"integer","nullable":true,"metadata":{}},{"name":"col4","type":"integer","nullable":true,"metadata":{}},{"name":"col5","type":"string","nullable":true,"metadata":{}},{"name":"col6","type":"float","nullable":true,"metadata":{}},{"name":"col7","type":"integer","nullable":true,"metadata":{}},{"name":"col8","type":"string","nullable":true,"metadata":{}},{"name":"col9","type":"string","nullable":true,"metadata":{}},{"name":"col10","type":"integer","nullable":true,"metadata":{}},{"name":"col11","type":"integer","nullable":true,"metadata":{}},{"name":"col12","type":"string","nullable":true,"metadata":{}},{"name":"col13","type":"float","nullable":true,"metadata":{}},{"name":"col14","type":"string","nullable":true,"metadata":{}},{"name":"col15","type":"string","nullable":true,"metadata":{}},{"name":"part_col1","type":"integer","nullable":true,"metadata":{}},{"name":"part_col2","type":"integer","nullable":true,"metadata":{}}]}',  |
|   'spark.sql.sources.schema.partCol.0'='part_col1',  |
|   'spark.sql.sources.schema.partCol.1'='part_col2',  |
|   'transient_lastDdlTime'='1587487456')            |
+----------------------------------------------------+

from above file I want to extract PARTITIONED BY details.

Desired output :

part_col1 , part_col2

and these PARTITIONED BY is not fixed , means for some other file it might contains 3 or more , so I want extract all the PARTITIONED BY.

All the values between PARTITIONED BY and ROW FORMAT SERDE , removing spaces "`" and data types!

Could you please help me with this ?

回答1:

sed -nr '/PARTITIONED BY/,/ROW FORMAT SERDE/p' a.txt|sed -nr '/`/p'|cut -d '`' -f 2|xargs -n 1 echo -n " "

回答2:

my $text = do { local $/; <DATA> };

my @partitioned = ();

$text=~s#PARTITIONED BY\s*\(([^\(\)]*)\)# my $fulcontent=$1; 
push (@partitioned, $1) while($fulcontent=~m/\`([^\`]+)\`/g);
($fulcontent);
#egs;

print join "\, ", @partitioned;

Output:

part_col1, part_col2

回答3:

When the layout of your result doesn't matter, you can ask sed to consider lines between a start and an end tag, and only print such a line when a field can be found between 2 backquotes.

sed -rn '/PARTITIONED BY/,/ROW FORMAT/s/.*`(.*)`.*/\1/p' file.txt

Combining the results in a line as desired can be done with

printf "%s , " $(sed -rn '/PARTITIONED BY/,/ROW FORMAT/s/.*`(.*)`.*/\1 /p' file.txt) |
   sed 's/ , $/\n/'

回答4:

Small perl script

• read whole file into $data variable
• select all between PARTITIONED BY (....)
• select into array only elements between `
• print result joined with ,

use strict;
use warnings;
use feature 'say';

my $data = do { local $/; <> };
my $re   = 'PARTITIONED BY \((.*?)\)';

$data =~ /$re/sg;

my @part = $1 =~ /`(.*?)`/sg;

say join ', ', @part;

来源：https://stackoverflow.com/questions/61352700/find-and-extract-value-after-specific-string-from-a-file-using-bash-shell-script