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MySQL Binlog

updated mysql

  • Most numeric fields use fixed-length encoding with little-endian byte order.

    • When you see 7a000000 in a hex dump, you read it as 0x0000007a = 122 in decimal.

  • The first event starts at position 4.

  • Every event in the binary log (version 4+) shares a common 19-byte header structure.

    • Timestamp, 4 bytes, Unix epoch seconds when the event was created
    • Event Type, 1 byte, Identifies how to interpret the payload
    • Server ID, 4 bytes, The server that originated this event (prevents circular replication)
    • Event Size, 4 bytes, Total size of this event in bytes (header + payload)
    • Next Position, 4 bytes, File offset where the next event begins
    • Flags, 2 bytes, Event-specific flags (bit field)