From c5111d865ea662564f3228f05f5b4d9a8eaffa95 Mon Sep 17 00:00:00 2001 From: Chandan Rajah Date: Thu, 6 Jun 2013 12:33:12 +0100 Subject: Cosmetic changes to Read Me --- README.md | 97 ++++++++++++++++++++++++++++++++++----------------------------- 1 file changed, 52 insertions(+), 45 deletions(-) diff --git a/README.md b/README.md index c2c2f76..c68d0b5 100644 --- a/README.md +++ b/README.md @@ -27,6 +27,7 @@ GET_LIST Requires the *keyList* parameter to be specified as well. (e.g.) + val hbs2 = new HBaseSource( "table_name", "quorum_name:2181", @@ -39,6 +40,7 @@ Requires the *keyList* parameter to be specified as well. Additionally, the *versions* parameter can be used to retrieve more than one version of the row. (e.g.) + val hbs2 = new HBaseSource( "table_name", "quorum_name:2181", @@ -60,35 +62,36 @@ if: - Neither provided -> All rows in table are returned. (e.g.) - val hbs4 = new HBaseSource( - "table_name", - "quorum_name:2181", - 'key, - Array("column_family"), - Array('column_name), - sourceMode = SourceMode.SCAN_RANGE, stopKey = "5003914") - .read - .write(Tsv(output.format("scan_range_to_end"))) - - val hbs5 = new HBaseSource( - "table_name", - "quorum_name:2181", - 'key, - Array("column_family"), - Array('column_name), - sourceMode = SourceMode.SCAN_RANGE, startKey = "5003914") - .read - .write(Tsv(output.format("scan_range_from_start"))) - - val hbs6 = new HBaseSource( - "table_name", - "quorum_name:2181", - 'key, - Array("column_family"), - Array('column_name), - sourceMode = SourceMode.SCAN_RANGE, startKey = "5003914", stopKey = "5004897") - .read - .write(Tsv(output.format("scan_range_between"))) + + val hbs4 = new HBaseSource( + "table_name", + "quorum_name:2181", + 'key, + Array("column_family"), + Array('column_name), + sourceMode = SourceMode.SCAN_RANGE, stopKey = "5003914") + .read + .write(Tsv(output.format("scan_range_to_end"))) + + val hbs5 = new HBaseSource( + "table_name", + "quorum_name:2181", + 'key, + Array("column_family"), + Array('column_name), + sourceMode = SourceMode.SCAN_RANGE, startKey = "5003914") + .read + .write(Tsv(output.format("scan_range_from_start"))) + + val hbs6 = new HBaseSource( + "table_name", + "quorum_name:2181", + 'key, + Array("column_family"), + Array('column_name), + sourceMode = SourceMode.SCAN_RANGE, startKey = "5003914", stopKey = "5004897") + .read + .write(Tsv(output.format("scan_range_between"))) SCAN_ALL @@ -96,6 +99,7 @@ SCAN_ALL Returns all rows in the table (e.g.) + val hbs2 = new HBaseSource( "table_name", "quorum_name:2181", @@ -112,13 +116,14 @@ HBaseSource supports writing at a particular time stamp i.e. a version. The time dimension can be added to the row by using the *timestamp* parameter. If the parameter is not present the current time is used. -(e.g.) - .write(new HBaseSource( "table_name", - "quorum_name:2181", - 'key, - TABLE_SCHEMA.tail.map((x: Symbol) => "data").toArray, - TABLE_SCHEMA.tail.map((x: Symbol) => new Fields(x.name)).toArray, - timestamp = Platform.currentTime )) +(e.g.) + + pipe.write(new HBaseSource( "table_name", + "quorum_name:2181", + 'key, + TABLE_SCHEMA.tail.map((x: Symbol) => "data").toArray, + TABLE_SCHEMA.tail.map((x: Symbol) => new Fields(x.name)).toArray, + timestamp = Platform.currentTime )) 3. Region Hot Spot Prevention @@ -128,9 +133,10 @@ Region hot spotting is a common problem with HBase. Spy Glass uses key prefix sa The row key is prefixed with the last byte followed by a '_' (underscore) character. (e.g.) -Original Row Key -> Becomes -SPYGLASS -> S_SPYGLASS -12345678 -> 8_12345678 + + Original Row Key -> Becomes + SPYGLASS -> S_SPYGLASS + 12345678 -> 8_12345678 Conversion to and from salted keys is done automatically. @@ -138,14 +144,15 @@ Setting the *useSalt* parameter to *true* enables this functionality (e.g.) - val TABLE_SCHEMA = List('key, 'salted, 'unsalted) + val TABLE_SCHEMA = List('key, 'salted, 'unsalted) + val hbase07 = - new HBaseSource( "table_name", - "quorum_name:2181", 'key, - TABLE_SCHEMA.tail.map((x: Symbol) => "data").toArray, - TABLE_SCHEMA.tail.map((x: Symbol) => new Fields(x.name)).toArray, - sourceMode = SourceMode.SCAN_RANGE, startKey = "11445", stopKey = "11455", useSalt = true, prefixList = "0123456789" ) + new HBaseSource( "table_name", + "quorum_name:2181", 'key, + TABLE_SCHEMA.tail.map((x: Symbol) => "data").toArray, + TABLE_SCHEMA.tail.map((x: Symbol) => new Fields(x.name)).toArray, + sourceMode = SourceMode.SCAN_RANGE, startKey = "11445", stopKey = "11455", useSalt = true, prefixList = "0123456789" ) .read // Convert from ImmutableBytesWritable to String -- cgit v1.2.3