Class PostgresqlSqlDialect


  • public class PostgresqlSqlDialect
    extends SqlDialect
    A SqlDialect implementation for the PostgreSQL database.
    • Field Detail

      • POSTGRESQL_TYPE_SYSTEM

        private static final RelDataTypeSystem POSTGRESQL_TYPE_SYSTEM
        PostgreSQL type system.
    • Constructor Detail

      • PostgresqlSqlDialect

        public PostgresqlSqlDialect​(SqlDialect.Context context)
        Creates a PostgresqlSqlDialect.
    • Method Detail

      • supportsCharSet

        public boolean supportsCharSet()
        Description copied from class: SqlDialect
        Returns whether the dialect supports character set names as part of a data type, for instance VARCHAR(30) CHARACTER SET `ISO-8859-1`.
        Overrides:
        supportsCharSet in class SqlDialect
      • requiresAliasForFromItems

        public boolean requiresAliasForFromItems()
        Description copied from class: SqlDialect
        Whether a sub-query in the FROM clause must have an alias.

        For example, in PostgreSQL, this query is legal:

        SELECT * FROM (SELECT * FROM Emp) As e

        but remove the alias e and it is not:

        SELECT * FROM (SELECT * FROM Emp)

        In Oracle, both queries are legal.

        Overrides:
        requiresAliasForFromItems in class SqlDialect
      • supportsNestedAggregations

        public boolean supportsNestedAggregations()
        Description copied from class: SqlDialect
        Returns whether the dialect supports nested aggregations, for instance SELECT SUM(SUM(1)) .
        Overrides:
        supportsNestedAggregations in class SqlDialect