![]() ![]() 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. If this is a migration, then you only need to do it once. So you will have to bite the bullet and adjust your code. 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) To deploy PostgreSQL in Red Hat OpenShift, we will use a modified image that initializes the database with a table and a Data Grid user with granted privileges to read from the table. So there is an obvious need to clarify what NULL is, how it works in different languages, and what the actual value is behind the NULL. In standard SQL, a Boolean value can be TRUE, FALSE, or NULL. PostgreSQL uses one byte for storing a boolean value in the database. In general all expressions involving NULL should yield NULL. We will use PostgreSQL to contain the table that will be loaded by Data Grid. What is NULL There is often some confusion about NULL value in PostgreSQL, as it is treated differently in different languages. PostgreSQL supports a single Boolean data type: BOOLEANthat can have three values: true, falseand NULL. In addition, you will suffer from a similar postgresql data error when completing the query structure. As a result, the system shows an error regardless of projectâs purpose and complexity. Because Oracle also is non-standard when the concatenation operator || is involved (just the other way round: null is treated as ''). The postgresql not working with several SQL queries bug happens because the tables contain invalid inputs and data. Null is returned only if all arguments are null. However, that will still not make Postgres behave like Oracle. 2 Answers Sorted by: 19 Use max (coalesce (logincount, 0)) to avoid NULLs According to Postgres docs (9.6): The COALESCE function returns the first of its arguments that is not null. ![]() If you really need this, you will have to convert empty strings to null when you save them (e.g. 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.Ä®dit: it just occurred to me what you might mean with "config level". Note that Oracle's behaviour is non-standard and no other DBMS treats '' the same as null in comparisons.Ä«tw: your condition WHERE ( SELECT '' FROM dual) IS NULL could be simplified to WHERE '' IS NULL. 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 = '' It has now been changed so that null values will return instead of the empty string.![]()
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