SQL Engine

💉jSQL generates default SQL syntax which is editable in tab SQL Engine, allowing to debug and optimize queries live for current identified engine.

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

The entire query roughly appears like the following:

character insertion  # input prefix like quote or parenthesis, eg. &p=', &p='), etc
  ${indices}:Normal or ${window}:Error+Stacked or ${boolean.mode}&${test}:Time+Blind
    ${injection}:all & ${window.char}:Multibit+Bittest & ${bit}
      ${database} ${table} ${fields}
        ${field.value}
          ${indice} & ${calibrator}:Normal
      ${limit}
        ${limit.value}
  ${window.char}

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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

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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: trigger Yes/No response for given single char ASCII code bit
  • Time: trigger Yes/No page delay for given single char ASCII code bit
  • Multibit: get specific result for given single char ASCII code bits group
  • Bit test — ${test}: return true when the bit of given ASCII code is 1, else return false

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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

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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

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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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