A, Hbase deleted
1. Create a table
2. Insert the larger data and view, note the timestamp value name2
3. The large that the timestamp delete name2
No data a.scan
b. marked with type = DeleteColumn logo
4. flush just delete the data in memory in memstore
Flush operation at this time, the value will delete all still in memory, but the deletion mark will not be deleted
5. If only the implementation major_compact, will really go to delete the data and delete "Delete mark"
二、Hbase get
rowkey not use single quotes, use double quotation
The same value, when not to use single quotes rowkey finding the data
Thirty-one kinds of quick query method
background:
When the storage of rowkey were Hash operation, we have been binary. Hbase by binary hexadecimal notation.
Beginning hexadecimal 0x, 16 hexadecimal binary to splice rowky Hbase can go inside to see drops, but less than the binary because the acquisition is not printing drops!
In order to pass a given string to Hbase query result, it can be achieved by a method for query purposes. After special to write code to do step by step out of the ... ...
a. appends hash string
// 拼接得到哈希串
String s="018ef624a1e72c393e8df54c078d2d461fcc43336f6ce4cde5a9874ae15af079";
int strs=s.toUpperCase().hashCode() & 0x7FFF ;
System.out.println((short)strs); //21621. B then hex 10 hex to give to give 21621: 5475 -> \ x54 \ x75,
c. splicing get rowkey query \ x54 \ x75
\ X54 \ x75018EF624A1E72C393E8DF54C078D2D461FCC43336F6CE4CDE5A9874AE15AF079
