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1. #POSTGRESQL COALESCE EMPTY STRING DRIVERS#
2. #POSTGRESQL COALESCE EMPTY STRING FULL#
3. #POSTGRESQL COALESCE EMPTY STRING CODE#

#POSTGRESQL COALESCE EMPTY STRING CODE#

If you need to support Postgres and Oracle from within the same code base, then you'll need to find a way to use different SQL depending on which database you connect to.

So you will have to bite the bullet and adjust your code. CREATE UNIQUE INDEX testupsertsolutionidx ON testupsert (name, status, COALESCE(testfield, '')) The empty string ('') is an obvious candidate for character types, but you can use any legal value that either never appears or can be folded with NULL according to your definition of 'unique'. However in Oracle 'foo'||null yields 'foo' whereas in every other database that yields null - and there is no way you can make Postgres do that (unless you change Postgres' source code)

One can guard against null errors within the query as follows: SELECT a FROM Author a WHERE :lastName IS NULL OR LOWER (a.lastName) :lastName.

#POSTGRESQL COALESCE EMPTY STRING DRIVERS#

In general all expressions involving NULL should yield NULL. The JDBC setNull with sql type parameter is fallback for legacy JDBC drivers that do not pass the JDBC Driver Test Suite. Because Oracle also is non-standard when the concatenation operator || is involved (just the other way round: null is treated as ''). However, that will still not make Postgres behave like Oracle.

If you really need this, you will have to convert empty strings to null when you save them (e.g. String and Number: only the regexpreplace function perfectly converts into integers. There is no configuration option that will make Postgres behave like Oracle here. There is no need to use a SELECT statement to use a constant value.Įdit: it just occurred to me what you might mean with "config level". Here is how COALESCE works with a non-NULL value for the first parameter: postgres select coalesce (1,null,2) coalesce - 1 (1 row) The COALESCE function finds the first non-NULL expression at the start, so it will always produce the same result regardless of what the remaining parameters contain.

#POSTGRESQL COALESCE EMPTY STRING FULL#

SELECT BAND.NAME AS BandName, CASE WHEN KBPLAYER.NAME '' THEN 'No Player' ELSE KBPLAYER.NAME END AS KeyboardPlayer FROM BAND FULL OUTER JOIN ( SELECT M.NAME, MO.BID FROM MEMBEROF MO, MEMBER M WHERE MO.

Note that Oracle's behaviour is non-standard and no other DBMS treats '' the same as null in comparisons.ītw: your condition WHERE ( SELECT '' FROM dual) IS NULL could be simplified to WHERE '' IS NULL. As per your comment to replace empty string to some text, the simple solution is to use case statement like below. Same statement executed from pgAdmin works fine.Well, if you don't want to use the obvious and simple solution nullif(., '') is null then you need to check for both an empty string and null: where the_column is null or the_column = '' Problem occurred only in this configuration:Įverything is working fine on few other configurations or when history is empty string. Hint: You will need to rewrite or cast the expression. Gives strange exception: 17/11/11 06:26:09:009 WARN util.JDBCExceptionReporter:100 - SQL Error: 0, SQLState: 42804ġ7/11/11 06:26:09:009 ERROR util.JDBCExceptionReporter:101 - ERROR: **column "history" is of type text but expression is of type bytea** Concatenating NULL values with non-NULL characters results in that character in Oracle, but NULL in PostgreSQL. Oracle reads empty strings as NULLs, while PostgreSQL treats them as empty. ) values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)") SUMMARY: This article discusses the differences between how Oracle and PostgreSQL evaluate NULL characters and empty strings.

(getEntityManager() returns spring injected EntityManager, database field history type is: text or varchar2(2000) Query query = getEntityManager().createNativeQuery("insert into table_name(., history. If entity.getHistory() is null following code snippet: