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How to change column data type in Apache Phoenix without losing HBase data?

I have an HBase installation with a bunch of existing tables, with a bunch of data in them (which I would not want to delete). I recently came across using Apache Phoenix to be able to query HBase data with syntax like SQL, and it is still brilliant. However, since I am still not completely familiar with the various data types and how they map to the Java types that I stored in HBase, sometimes I get it wrong. If I had a HBase column that I saved as

Bytes.toBytes(Long long)

and I accidentally created my Phoenix table as a varchar, how can I now change the Phoenix column without losing all my data? If i do

alter table "mytable" add "myfamily"."mycolumn" unsigned_long

and then

alter table "mytable" drop column "mycolumn"

and then

alter table "mytable" add "myfamily"."mycolumn" varchar

all my HBase data is deleted from the "mycolumn" column! What is the best way to get around this?

phoenix.schema.dropMetaData

false, , , , . - , Squirrel Phoenix, false? ?

!

1

Phoenix , system.catalog, .

upsert into system.catalog (table_name, column_name, column_family, data_type) values ('mytable','mycolumn','mycf',3)

mycolumn . , mytable, mycolumn - unsigned_long. , HBase?

FYI:

COLUMN_NAME DATA_TYPE
MYTINYINT   -6
MYBIGINT    -5
MYDECIMAL   3
MYINTEGER   4
MYFLOAT 6
MYDOUBLE    8
MYUINTEGER  9
MYULONG 10
MYUTINYINT  11
MYVARCHAR   12
ROWID   12
MYUFLOAT    14
MYUDOUBLE   15
MYBOOLEAN   16
MYUTIME 18
MYUDATE 19
MYUTIMESTAMP    19
MYDATE  91
MYTIME  92
MYTIMESTAMP 93

2

, Phoenix, HBase, SYSTEM.CATALOG SYSTEM.STATS. . , - HBase!

+4
2

Phoenix HBase, SYSTEM_CATALOG. phoenix.schema.dropMetaData
, ALTER.

false, , , TableAlreadyExistsException.

+1

, , .

ALTER TABLE tablename DROP COLUMN columnname;
ALTER TABLE tablename ADD columnname varchar(100);
0

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