Class: RubynCode::DB::Schema

Inherits:
Object
  • Object
show all
Defined in:
lib/rubyn_code/db/schema.rb

Overview

Provides schema introspection helpers and version checking for the database.

Instance Method Summary collapse

Constructor Details

#initialize(connection) ⇒ Schema

Returns a new instance of Schema.

Parameters:

  • connection (Connection) —

    the database connection



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# File 'lib/rubyn_code/db/schema.rb', line 9

def initialize(connection)
  @connection = connection
end

Instance Method Details

#applied_versions ⇒ Array<Integer>

Returns all applied migration versions in order.

Returns:

  • (Array<Integer>) 


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# File 'lib/rubyn_code/db/schema.rb', line 28

def applied_versions
  @connection.query(
    'SELECT version FROM schema_migrations ORDER BY version'
  ).to_a.map { |row| row['version'] }
rescue StandardError
  []
end

#columns(table_name) ⇒ Array<Hash>

Returns column information for the given table.

Parameters:

  • table_name (String)

Returns:

  • (Array<Hash>) —

    each hash has keys: cid, name, type, notnull, dflt_value, pk



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# File 'lib/rubyn_code/db/schema.rb', line 63

def columns(table_name)
  @connection.query("PRAGMA table_info(#{quote_identifier(table_name)})").to_a
end

#current_version ⇒ Integer?

Returns the current schema version (highest applied migration).

Returns:

  • (Integer, nil) —

    the version number, or nil if no migrations applied



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# File 'lib/rubyn_code/db/schema.rb', line 16

def current_version
  row = @connection.query(
    'SELECT MAX(version) AS max_version FROM schema_migrations'
  ).to_a.first
  row && row['max_version']
rescue StandardError
  nil
end

#indexes(table_name) ⇒ Array<Hash>

Returns index information for the given table.

Parameters:

  • table_name (String)

Returns:

  • (Array<Hash>) 


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# File 'lib/rubyn_code/db/schema.rb', line 71

def indexes(table_name)
  @connection.query("PRAGMA index_list(#{quote_identifier(table_name)})").to_a
end

#table_exists?(table_name) ⇒ Boolean

Checks whether a given table exists in the database.

Parameters:

  • table_name (String)

Returns:

  • (Boolean) 


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# File 'lib/rubyn_code/db/schema.rb', line 79

def table_exists?(table_name)
  rows = @connection.query(
    "SELECT 1 FROM sqlite_master WHERE type = 'table' AND name = ?",
    [table_name]
  ).to_a
  !rows.empty?
end

#tables ⇒ Array<String>

Returns a list of table names in the database (excluding internal SQLite tables).

Returns:

  • (Array<String>) 


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# File 'lib/rubyn_code/db/schema.rb', line 52

def tables
  @connection.query(
    "SELECT name FROM sqlite_master WHERE type = 'table' " \
    "AND name NOT LIKE 'sqlite_%' ORDER BY name"
  ).to_a.map { |row| row['name'] }
end

#up_to_date?(migrator) ⇒ Boolean

Returns true if the schema is up to date with all available migrations.

Parameters:

Returns:

  • (Boolean) 


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# File 'lib/rubyn_code/db/schema.rb', line 91

def up_to_date?(migrator)
  migrator.pending_migrations.empty?
end

#version_applied?(version) ⇒ Boolean

Checks whether a specific migration version has been applied.

Parameters:

  • version (Integer)

Returns:

  • (Boolean) 


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# File 'lib/rubyn_code/db/schema.rb', line 40

def version_applied?(version)
  rows = @connection.query(
    'SELECT 1 FROM schema_migrations WHERE version = ?', [version]
  ).to_a
  !rows.empty?
rescue StandardError
  false
end