presario 1500

pagesize 30; 3 User name switching: such as Conn System/tiger Conn Sys/change_on_install as SYSDBA (note that Superuser is added as SYSDBA at the back) 4 looking for a normal user's table under Superuser is not found. You must look for such as SELECT * from Scott.emp (EMP table under normal user) 5 View current is that user login: show user; 6 See how many tables: SELECT * from tab; (note that tables under different users are different) 7 View the structure of the table: DESC EMP (EMP is the ta

The PHP timestamp uses the instance code. We will surely encounter this situation: Bank A and Bank B open your account almost simultaneously and see the original 1000 yuan deposit in your account, then both banks want to add 5 to your account. we will certainly encounter this situation: bank A and Bank B open your account almost simultaneously and see the original 1000 yuan deposit in your account. then both banks want to add 500 yuan in deposits to your account. Then, Bank A will change 1000 yu

characteristics of the network, and is responsible for transmitting 0 and 1 electrical signals. 3. Link Layer 3.1 Definition 0 and 1 alone have no meaning. You must specify the interpretation method: How many electric signals are counted in a group? What is the significance of each signal bit? This is the function of "link layer". It is above the "entity layer" and determines the grouping method of 0 and 1. 3.2 Ethernet protocol In the early days, each company had its own electric signal groupi

6506> (enable) show configThis command shows non-default invocations only.Use 'show config all' to show both default and non-default config.........................................................Begin!# ***** NON-DEFAULT CONFIGURATION *****!!# Time: Thu Jan 4 2001, 08:27:22!# Version 5.4 (3) # Software version!Set password $2 $ lnsk $ mgJ84scE. A51hpr0Zbdfv/# encrypted telnet passwordSet enablepass $2 $ RFAC $ BDgIVKdk3gl1RD4. DaNcu. # encrypted enable password!# SystemSet system name 6506 # sy

6506> (enable) show configThis command shows non-default invocations only.Use show config all to show both default and non-default config.........................................................Begin!# ***** NON-DEFAULT CONFIGURATION *****!!# Time: Thu Jan 4 2001, 08:27:22!# Version 5.4 (3) # Software version!Set password $2 $ lnsk $ mgJ84scE. A51hpr0Zbdfv/# encrypted telnet passwordSet enablepass $2 $ RFAC $ BDgIVKdk3gl1RD4. DaNcu. # encrypted enable password!# SystemSet system name 6506 # syst

As shown in the preceding example, we will first introduce the timestamp. The timestamp is a set of random numbers generated based on the current system time. Timestamp is generally used as a basis for determining data uniqueness. Next we will introduce how we can use timestamps. We will surely encounter this situation: Bank A and Bank B open your account almost simultaneously and see the original 1000 yuan deposit in your account, then both banks want to add a deposit of 500 yuan to your accoun

I was in the video with the mediarecorder of the problem of the synchronization of videos and audio, asked some people after the feeling should be no time stamp, have always felt that the time stamp is to the user to see a data, check the discovery is not, the following is reproduced. We hope to be useful to you:Let's first introduce you to what a timestamp is. in layman's terms, a timestamp is a set of random numbers generated from the current system time.Timestamps are generally used as an i

transmits the first packet (3000-3499), so the receiver finds a duplicate, and then returns a sack=3000-3500 because the ACK is 4000 means that all data before 4000 is received. So this SACK is d-sack--is designed to tell the sender that I received duplicate data, and our sender also know that the packet is not lost, the missing is the ACK packet.? 1234567 Transmitted Received ACK SentSegment Segment (Including SACK Blocks)3000-3499 3000-3499 3500 (ACK dropped)3500-3999 3500

When it comes to UDP programming, the easiest thing to think about is how many bytes are sent at a time? Of course, this does not have the only answer, compared to different systems, different requirements, the answer is not the same, here just like the ICQ type of sending chat messages to analyze, for other cases, may also get a little help: First of all, we know that tcp/ IP is generally considered to be a four-layer protocol system, including link layer, network layer, Transport layer, appl

Brain Map: SocketFrom the length of the UDP datagram.UDP belongs to the transport layer in the network model. Let's look at the next step from the bottom to the previous step:Theoretically, the maximum IP packet (packet) allowed by the IP protocol is 2^16=65535 (the total IP packet length is 16 bits):But! The length of the Ethernet (Ethernet) data frame must be between 46-1500 bytes, which is determined by the physical characteristics of the Ethernet.