SQL Engine

💉jSQL generates default SQL syntax based on a template which is editable in tab SQL Engine, allowing to live-debug and optimize queries on the fly for current identified engine.

Any SQL part is defined by a unique ${tag} and all tags are replaced by its concrete value in the final query.

The entire template is roughly like the following:

character insertion layer                                    # input prefix
  ${indices}:Normal or ${boolean.mode} & ${test}:Time+Blind  # strategy layer
    ${window}                                                # chars substring
      ${window.char}:Multibit+Bittest & ${bit}               # chars position index
        ${injection}:all                                     # main select
          ${database} ${table} ${fields}                     # all fields with main from
            ${field.value}                                   # single field syntax
              ${indice} & ${calibrator}                      # Normal specific
          ${limit}                                           # rows position
            ${limit.value}                                   # rows position index

Structure — schema content — ${injection}

• Database: get names with number of tables
• Tables: get names with number of rows
• Columns: get names
• Rows: get de-duplicated rows
  • Field: single column name, all fields are concatenated into ${fields} with separator
  • Field Separator: added between fields to separate column values
• Metadata: get engine info like version and current user

Strategy — high level syntax

• Normal: apply union-based select
• Stacked: apply stack select
• Error: apply exception trigger that includes the result
• Boolean — bitwise strategies
  • Mode — ${boolean.mode}: use AND/OR depending on the initial query state (eg. where 1=1 AND, where 1=0 OR)
  • Blind: get result Yes/No for given bit from ASCII code of a single char
  • Time: get delay Yes/No for given bit from ASCII code of a single char
  • Multibit: get specific result for given bits from ASCII code of a single char
  • Bit test — ${test}: return true when the bit of given ASCII code is 1, else return false

Configuration — other parts

• Char Sliding Window — ${window.char}: set a substring of data
• Rows Sliding Window — ${limit}: set rows starting at specific position (see LIMIT)
• Limit start index — ${limit.value}: set LIMIT initial position, some engine starts at 0 and some at 1
• Capacity — ${capacity}: set specific Normal query to measure indexes response size
• Calibrator — ${calibrator}: repeat given char for Normal capacity measure
• Failsafe: set Normal index with N0+1 form
• End comment: set SQL comment to ignore internal query remaining parts

Fingerprint — identify engine and character insertion

• Order by: set wrong column index to trigger specific engine error
• Order by error: expected engine error when order by index is wrong
• String error: expected SQL syntax error when query is incorrect
• Truthy: list of predicate checked as true by engine
• Falsy: list of predicate checked as false by engine

File

• Privilege: get current user's read permission
• Read: get file content to read
• Write body: set file content to write
• Write path: set file path to write

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