bytea

问题 I have PostgreSQL database and there is column 'image' with datatype 'bytea'. I cannot modify columns or database configurations. JPA annotated POJO contains followign mapping @Column(name="image") private byte[] image; The returned data is in following format (this is just a sample) WF5ClN6RlpLZ0hJTUdNQ1FJWmkwcFVGSUdNQ0lDWUE5TUEvanRFeElwK2x0M2tBQUFBQVNVVk9SSzVDWUlJPQo= When I write this data to file (.jpeg) photo viewer says "this is corrupted file". I also understand that actual image byte

问题 I have PostgreSQL database and there is column 'image' with datatype 'bytea'. I cannot modify columns or database configurations. JPA annotated POJO contains followign mapping @Column(name="image") private byte[] image; The returned data is in following format (this is just a sample) WF5ClN6RlpLZ0hJTUdNQ1FJWmkwcFVGSUdNQ0lDWUE5TUEvanRFeElwK2x0M2tBQUFBQVNVVk9SSzVDWUlJPQo= When I write this data to file (.jpeg) photo viewer says "this is corrupted file". I also understand that actual image byte

问题 I have PostgreSQL database and there is column 'image' with datatype 'bytea'. I cannot modify columns or database configurations. JPA annotated POJO contains followign mapping @Column(name="image") private byte[] image; The returned data is in following format (this is just a sample) WF5ClN6RlpLZ0hJTUdNQ1FJWmkwcFVGSUdNQ0lDWUE5TUEvanRFeElwK2x0M2tBQUFBQVNVVk9SSzVDWUlJPQo= When I write this data to file (.jpeg) photo viewer says "this is corrupted file". I also understand that actual image byte

问题 I have some image data stored in a PostgreSQL database table column as bytea. I also have metadata about the data for use in interpreting it, relevant ones being image dimensions and class. Classes include int16, uint16. I cannot find any information on interpreting signed/unsigned ints correctly in R. I am using RPostgreSQL to pull the data into R and I want to view the image in R. MWE: # fakeDataQuery <- dbGetQuery(conn, # 'select byteArray, ImageSize, ImageClass from table where id = 1') #

问题 I have some image data stored in a PostgreSQL database table column as bytea. I also have metadata about the data for use in interpreting it, relevant ones being image dimensions and class. Classes include int16, uint16. I cannot find any information on interpreting signed/unsigned ints correctly in R. I am using RPostgreSQL to pull the data into R and I want to view the image in R. MWE: # fakeDataQuery <- dbGetQuery(conn, # 'select byteArray, ImageSize, ImageClass from table where id = 1') #

问题 I am trying to execute the code: Connect to the server library('RPostgreSQL', quietly = TRUE) kHostName <- '...' kPort <- '5432' kDBName <- '...' kUser <- '...' kPassword <- '...' drv <- dbDriver("PostgreSQL") con <- dbConnect(drv, host = kHostName, port = kPort, dbname = kDBName, user = kUser, password = kPassword) The following part of the code is taken from https://groups.google.com/forum/#!topic/rpostgresql-dev/lPPmS8yeP9w and https://github.com/codeinthehole/rpostgresql/blob/master

问题 My application (developed in Delphi and ZEOS components) uses PostgreSQL 8.4 and stores some thumbnail images into a bytea column. I want to migrate to PostgreSQL 9.2 and have restored the dump and everything works fine except when I try to retrieve those images: Postgres 9.2 uses hex for output representation instead of escape used in Postgres 8.4. There are two possible solutions: Change the Postgres 9.2 settings for escape representation or change the hex string in binary data via

问题 My application (developed in Delphi and ZEOS components) uses PostgreSQL 8.4 and stores some thumbnail images into a bytea column. I want to migrate to PostgreSQL 9.2 and have restored the dump and everything works fine except when I try to retrieve those images: Postgres 9.2 uses hex for output representation instead of escape used in Postgres 8.4. There are two possible solutions: Change the Postgres 9.2 settings for escape representation or change the hex string in binary data via

问题 I'm trying to insert objects of type Book into a database, and one of the columns is specified as date, but according to this exception: Caused by: org.postgresql.util.PSQLException: ERROR: column "publish_date" is of type date but expression is of type bytea Hint: You will need to rewrite or cast the expression. Position: 94 at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2412) at org.postgresql.core.v3.QueryExecutorImpl.processResults

问题 I'm trying to insert objects of type Book into a database, and one of the columns is specified as date, but according to this exception: Caused by: org.postgresql.util.PSQLException: ERROR: column "publish_date" is of type date but expression is of type bytea Hint: You will need to rewrite or cast the expression. Position: 94 at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2412) at org.postgresql.core.v3.QueryExecutorImpl.processResults