Ingres9 sequences

src/NHibernate/Dialect/Ingres9Dialect.cs

@@ -2,67 +2,102 @@
 
 namespace NHibernate.Dialect
 {
-	public class Ingres9Dialect : IngresDialect
-	{
-		/// <summary>
-		/// Does this Dialect have some kind of <c>LIMIT</c> syntax?
-		/// </summary>
-		/// <value>
-		/// False, unless overridden.
-		/// </value>
-		public override bool SupportsLimit
-		{
-			get { return true; }
-		}
+    public class Ingres9Dialect : IngresDialect
+    {
+        /// <summary>
+        /// Does this Dialect have some kind of <c>LIMIT</c> syntax?
+        /// </summary>
+        /// <value>
+        /// False, unless overridden.
+        /// </value>
+        public override bool SupportsLimit
+        {
+            get { return true; }
+        }
 
-		/// <summary>
-		/// Can parameters be used for a statement containing a LIMIT?
-		/// </summary>
-		public override bool SupportsVariableLimit
-		{
-			get { return false; }
-		}
+        /// <summary>
+        /// Can parameters be used for a statement containing a LIMIT?
+        /// </summary>
+        public override bool SupportsVariableLimit
+        {
+            get { return false; }
+        }
 
-		/// <summary>
-		/// Does this Dialect support an offset?
-		/// </summary>
-		public override bool SupportsLimitOffset
-		{
-			get { return true; }
-		}
-
-		/// <summary>
-		/// Attempts to add a <c>LIMIT</c> clause to the given SQL <c>SELECT</c>.
-		/// Expects any database-specific offset and limit adjustments to have already been performed (ex. UseMaxForLimit, OffsetStartsAtOne).
-		/// </summary>
-		/// <param name="queryString">The <see cref="SqlString"/> to base the limit query off.</param>
-		/// <param name="offset">Offset of the first row to be returned by the query.  This may be represented as a parameter, a string literal, or a null value if no limit is requested.  This should have already been adjusted to account for OffsetStartsAtOne.</param>
-		/// <param name="limit">Maximum number of rows to be returned by the query.  This may be represented as a parameter, a string literal, or a null value if no offset is requested.  This should have already been adjusted to account for UseMaxForLimit.</param>
-		/// <returns>
-		/// A new <see cref="SqlString"/> that contains the <c>LIMIT</c> clause. Returns <c>null</c>
-		/// if <paramref name="queryString"/> represents a SQL statement to which a limit clause cannot be added,
-		/// for example when the query string is custom SQL invoking a stored procedure.
-		/// </returns>
-		public override SqlString GetLimitString(SqlString queryString, SqlString offset, SqlString limit)
-		{
-			SqlStringBuilder pagingBuilder = new SqlStringBuilder();
-			pagingBuilder.Add(queryString);
+        /// <summary>
+        /// Does this Dialect support an offset?
+        /// </summary>
+        public override bool SupportsLimitOffset
+        {
+            get { return true; }
+        }
 
-			if (offset != null)
-			{
-				pagingBuilder.Add(" offset ");
-				pagingBuilder.Add(offset);
-			}
+        /// <summary>
+        /// Does this dialect support sequences?
+        /// </summary>
+        public override bool SupportsSequences
+        {
+            get { return true; }
+        }
 
-			if (limit != null)
-			{
-				pagingBuilder.Add(" fetch ");
-				pagingBuilder.Add(offset != null ? "next " : "first ");
-				pagingBuilder.Add(limit);
-				pagingBuilder.Add(" rows only");
-			}
+        /// <summary>
+        /// Attempts to add a <c>LIMIT</c> clause to the given SQL <c>SELECT</c>.
+        /// Expects any database-specific offset and limit adjustments to have already been performed (ex. UseMaxForLimit, OffsetStartsAtOne).
+        /// </summary>
+        /// <param name="queryString">The <see cref="SqlString"/> to base the limit query off.</param>
+        /// <param name="offset">Offset of the first row to be returned by the query.  This may be represented as a parameter, a string literal, or a null value if no limit is requested.  This should have already been adjusted to account for OffsetStartsAtOne.</param>
+        /// <param name="limit">Maximum number of rows to be returned by the query.  This may be represented as a parameter, a string literal, or a null value if no offset is requested.  This should have already been adjusted to account for UseMaxForLimit.</param>
+        /// <returns>
+        /// A new <see cref="SqlString"/> that contains the <c>LIMIT</c> clause. Returns <c>null</c>
+        /// if <paramref name="queryString"/> represents a SQL statement to which a limit clause cannot be added,
+        /// for example when the query string is custom SQL invoking a stored procedure.
+        /// </returns>
+        public override SqlString GetLimitString(SqlString queryString, SqlString offset, SqlString limit)
+        {
+            SqlStringBuilder pagingBuilder = new SqlStringBuilder();
+            pagingBuilder.Add(queryString);
 
-			return pagingBuilder.ToSqlString();
-		}
-	}
+            if (offset != null)
+            {
+                pagingBuilder.Add(" offset ");
+                pagingBuilder.Add(offset);
+            }
+
+            if (limit != null)
+            {
+                pagingBuilder.Add(" fetch ");
+                pagingBuilder.Add(offset != null ? "next " : "first ");
+                pagingBuilder.Add(limit);
+                pagingBuilder.Add(" rows only");
+            }
+
+            return pagingBuilder.ToSqlString();
+        }
+
+        /// <summary> 
+        /// Generate the appropriate select statement to to retreive the next value
+        /// of a sequence.
+        /// </summary>
+        /// <param name="sequenceName">the name of the sequence </param>
+        /// <returns> String The "nextval" select string. </returns>
+        /// <remarks>This should be a "stand alone" select statement.</remarks>
+        public override string GetSequenceNextValString(string sequenceName)
+        {
+            return "select " + GetSelectSequenceNextValString(sequenceName) + " as seq";
+        }
+
+        /// <summary> 
+        /// Generate the select expression fragment that will retrieve the next
+        /// value of a sequence as part of another (typically DML) statement.
+        /// </summary>
+        /// <param name="sequenceName">the name of the sequence </param>
+        /// <returns> The "nextval" fragment. </returns>
+        /// <remarks>
+        /// This differs from <see cref="GetSequenceNextValString"/> in that this
+        /// should return an expression usable within another statement.
+        /// </remarks>
+        public override string GetSelectSequenceNextValString(string sequenceName)
+        {
+            return "next value for " + sequenceName;
+        }
+    }
 }