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copied!<p>Just a random try:</p> <p>Transform your GetBaseLogQuery function to :</p> <pre><code>Func<EncDataContext,IQueryable<Log>> getBaseLogQuery; public Expression<Func<EncDataContext,IQueryable<Log>>> GetBaseLogQuery(EncDataContext context) { if(getBaseLogQuery==null) getBaseLogQuery=GetBaseLogQueryExpr().Compile(); return getBaseLogQuery(context); } public Expression<Func<EncDataContext,IQueryable<Log>>> GetBaseLogQueryExpr() { return context=>from pl in context.DbLog ..... etc ....; // contrainst: this MUST be a lambda. } </code></pre> <p>And then, create this function:</p> <pre><code>static Expression<Func<EncDataContext, TArg1, TArg2, TReturn>> WrapQuery<T, TArg1, TArg2, TReturn>(Expression<Func<IQueryable<T>, TArg1, TArg2, TReturn>> todo) { var baseQuery = GetBaseLogQueryExpr(); var newQueryExpression = new ReplaceVisitor(todo.Parameters.First(), baseQuery.Body).Visit(todo.Body); List<ParameterExpression> @params = todo.Parameters.Skip(1).ToList(); @params.Insert(0, baseQuery.Parameters.First()); return Expression.Lambda<Func<EncDataContext, TArg1, TArg2, TReturn>>(newQueryExpression, @params.ToArray()); } </code></pre> <p>using class</p> <pre><code> class ReplaceVisitor : ExpressionVisitor { readonly Expression to; readonly ParameterExpression @from; public ReplaceVisitor(ParameterExpression from, Expression to) { this.to = to; this.@from = @from; } public override Expression Visit(Expression node) { if (node == @from) return @to; return base.Visit(node); } } </code></pre> <p>You can create your query extension like this:</p> <pre><code>var resultExpr = WrapQuery((query,orgId,uid)=>query.SingleOrDefault(pl => pl.OrganizationId == organizationId && pl.UniqueID == uniqueId)); _loadLogByUniqueId = CompiledQuery.Compile(resultExpr); </code></pre> <p>Not tested.</p> <p>Pros: Can be reused.</p> <p>Cons: You'll have to rewrite a new WrapQuery function for each parameter count (that's quite easy, though... just a dump copy/paste/adapt)</p>

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