return nil, ErrNegativeCount
	}

	b.lastByte = -1
	b.lastRuneSize = -1

	for b.w-b.r < n && b.w-b.r < len(b.buf) && b.err == nil {
		b.fill() // b.w-b.r < len(b.buf) => buffer is not full
	}

	if n > len(b.buf) {
		return b.buf[b.r:b.w], ErrBufferFull
	}

	// 0 <= n <= len(b.buf)
	var err error
	if avail := b.w - b.r; avail < n {
		// not enough data in buffer
		n = avail

					n := 0
					var latency int64
					managers := grid.Managers
					hosts := grid.Hosts
					for pb.Next() {
						// Pick a random manager.
						src, dst := rng.Intn(len(managers)), rng.Intn(len(managers))
						if src == dst {
							dst = (dst + 1) % len(managers)
						}
						local := managers[src]
						conn := local.Connection(hosts[dst])
						if conn == nil {
							b.Fatal("No connection")
						}

		}

		builder.WriteQuoted(column)
	}

	if len(groupBy.Having) > 0 {
		builder.WriteString(" HAVING ")
		Where{Exprs: groupBy.Having}.Build(builder)
	}
}

// MergeClause merge group by clause
func (groupBy GroupBy) MergeClause(clause *Clause) {
	if v, ok := clause.Expression.(GroupBy); ok {
		copiedColumns := make([]Column, len(v.Columns))
		copy(copiedColumns, v.Columns)

    }

    /* This method will not return until len bytes have been read
     * or the stream has been closed.
     */

    public synchronized int read( byte[] b, int off, int len ) throws IOException {
        if( len == 0 ) {
            return 0;
        }
        tot = 0;

        while( true ) {
            while( bip > 0 ) {
                n = in.read( b, off, Math.min( len, bip ));
                if( n == -1 ) {

		if _, err := strconv.Atoi(s); err != nil {
			if s == "" && len(args) == 0 {
				return nil
			}

			if len(args) == 0 || (len(args) > 0 && strings.Contains(s, "?")) {
				// looks like a where condition
				return []clause.Expression{clause.Expr{SQL: s, Vars: args}}
			}

			if len(args) > 0 && strings.Contains(s, "@") {
				// looks like a named query

        align(4);
        int i = this.index;
        int len = s.length();
        Encdec.enc_uint32le(len + 1, this.buf, i);
        i += 4;
        Encdec.enc_uint32le(0, this.buf, i);
        i += 4;
        Encdec.enc_uint32le(len + 1, this.buf, i);
        i += 4;
        System.arraycopy(Strings.getUNIBytes(s), 0, this.buf, i, len * 2);
        i += len * 2;
        this.buf[ i++ ] = (byte) '\0';

     * ServerMessageBlock.java because the arguments are different, however
     * one might be able to reduce this.
     */
    
                if( len > 0 && src[srcIndex + len - 1] == '\0' ) {
                    len--;
                }
                str = new String( src, srcIndex, len, ServerMessageBlock.OEM_ENCODING );
            }
        } catch( UnsupportedEncodingException uee ) {
            if( log.level > 1 )

            int id = Encdec.dec_uint16le(type2token, ri);
            int len = Encdec.dec_uint16le(type2token, ri + 2);
            ri += 4;
            if (id == 0 || (ri + len) > type2token.length) {
                break;
            } else if (id == id0) {
                try {
                    return new String(type2token, ri, len, SmbConstants.UNI_ENCODING);

			zb0002, err = dc.ReadMapHeader()
			if err != nil {
				err = msgp.WrapError(err, "Tiers")
				return
			}
			if z.Tiers == nil {
				z.Tiers = make(map[string]madmin.TierConfig, zb0002)
			} else if len(z.Tiers) > 0 {
				for key := range z.Tiers {
					delete(z.Tiers, key)
				}
			}
			for zb0002 > 0 {
				zb0002--
				var za0001 string
				var za0002 madmin.TierConfig
				za0001, err = dc.ReadString()

        }

        if ( isRetainPayload() ) {
            this.rawPayload = new byte[len];
            System.arraycopy(dst, start, this.rawPayload, 0, len);
        }

        return len;
    }


    protected static final int size8 ( int size ) {
        return size8(size, 0);
    }