AWK高级用法之打印匹配行的上一行

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最近对数据处理很感兴趣，一直在研究Linux三剑客：grep AWK sed ，下面举个实际工作中遇到的一个小实例，联用三大文本处理剑客。

已知table.txt文件，cat查看文件内容如下，其实也就是我查询数据库中部分表的状态。

[pc@glusterfs-srv-01 ~]$ cat table.txt
*************************** 15. row ***************************
           Name: procs_priv
         Engine: MyISAM
        Version: 10
     Row_format: Fixed
           Rows: 0
Avg_row_length: 0
    Data_length: 0
Max_data_length: 239253730204057599
   Index_length: 4096
      Data_free: 0
Auto_increment: NULL
    Create_time: 2016-09-19 01:38:11
    Update_time: 2016-09-19 01:38:11
     Check_time: NULL
      Collation: utf8_bin
       Checksum: NULL
Create_options:
        Comment: Procedure privileges
*************************** 16. row ***************************
           Name: proxies_priv
         Engine: MyISAM
        Version: 10
     Row_format: Fixed
           Rows: 2
Avg_row_length: 693
    Data_length: 1386
Max_data_length: 195062158860484607
   Index_length: 5120
      Data_free: 0
Auto_increment: NULL
    Create_time: 2016-09-19 01:38:11
    Update_time: 2016-09-19 01:38:11
     Check_time: 2016-09-19 01:38:11
      Collation: utf8_bin
       Checksum: NULL
Create_options:
        Comment: User proxy privileges
*************************** 17. row ***************************
           Name: servers
         Engine: MyISAM
        Version: 10
     Row_format: Fixed
           Rows: 0
Avg_row_length: 0
    Data_length: 0
Max_data_length: 433752939111120895
   Index_length: 1024
      Data_free: 0
Auto_increment: NULL
    Create_time: 2016-10-19 01:38:11
    Update_time: 2016-09-19 01:38:11
     Check_time: NULL
      Collation: utf8_general_ci
       Checksum: NULL
Create_options:
        Comment: MySQL Foreign Servers table
*************************** 18. row ***************************
           Name: slave_master_info
         Engine: InnoDB
        Version: 10
     Row_format: Compact
           Rows: 0
Avg_row_length: 0
    Data_length: 16384
Max_data_length: 0
   Index_length: 0
      Data_free: 0
Auto_increment: NULL
    Create_time: 2016-03-19 01:38:15
    Update_time: NULL
     Check_time: NULL
      Collation: utf8_general_ci
       Checksum: NULL
Create_options: stats_persistent=0
        Comment: Master Information
*************************** 19. row ***************************
           Name: slave_relay_log_info
         Engine: InnoDB
        Version: 10
     Row_format: Compact
           Rows: 0
Avg_row_length: 0
    Data_length: 16384
Max_data_length: 0
   Index_length: 0
      Data_free: 0
Auto_increment: NULL
    Create_time: 2016-04-19 01:38:15
    Update_time: NULL
     Check_time: NULL
      Collation: utf8_general_ci
       Checksum: NULL
Create_options: stats_persistent=0
        Comment: Relay Log Information

要求：打印出在2016年8月份之后创建的数据库表名

答案： cat table.txt | awk 'NF' | grep -iE 'name|create_time' | awk -F':' '{ print $2}' | sed -e 's/^[[:space:]]//’ | awk -F- ‘/^[[:alpha:]]/ {a=$0;next} {if ($2>7) print a}'

shell下运行结果如下，