public SqlExpression Translate(SqlExpression instance, MethodInfo method, IReadOnlyList <SqlExpression> arguments, IDiagnosticsLogger <DbLoggerCategory.Query> logger)
{
if (!method.Equals(StartsWithMethod))
{
return(null);
}
var patternExpression = arguments[0];
var startsWithExpression = _fbSqlExpressionFactory.AndAlso(
_fbSqlExpressionFactory.Like(
instance,
_fbSqlExpressionFactory.Add(patternExpression, _fbSqlExpressionFactory.Constant("%"))),
_fbSqlExpressionFactory.Equal(
_fbSqlExpressionFactory.Function(
"LEFT",
new[] {
instance,
_fbSqlExpressionFactory.Function(
"CHAR_LENGTH",
new[] { patternExpression },
true,
new[] { true },
typeof(int))
},
true,
new[] { true, true },
instance.Type),
patternExpression));
return(patternExpression is SqlConstantExpression sqlConstantExpression
? (string)sqlConstantExpression.Value == string.Empty
? (SqlExpression)_fbSqlExpressionFactory.Constant(true)
: startsWithExpression
: _fbSqlExpressionFactory.OrElse(
startsWithExpression,
_fbSqlExpressionFactory.Equal(
patternExpression,
_fbSqlExpressionFactory.Constant(string.Empty))));
}