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 identified with a unique ${tag} that is replaced with concrete value in the final query.

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Structure — schema content

• 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 — syntax for Time, Blind, Multibit, Error, Stacked, Normal

• Normal: apply union-based select
• Stacked: apply stack select
• Error: apply exception trigger including the result
• Boolean — bitwise strategies
  • Mode: use AND/OR depending on the initial query state (eg. where 1=1 AND, where 1=0 OR)
  • Blind: trigger Yes/No response from bits of ASCII code for a single char
  • Time: trigger Yes/No page delay from bits of ASCII code for a single char
  • Multibit: get specific result for multiple bits of ASCII code for a single char
  • Bit 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: set a substring of data
• Rows Sliding Window: set rows starting at specific position (see LIMIT)
• Limit start index: set LIMIT initial position, some engine starts at 0 and some at 1
• Capacity: set specific Normal query to measure indexes response size
• 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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