Module: ClickHouseHelper

Defined in:
lib/db/clickhouse.rb

Constant Summary collapse

CLICKHOUSE_PG_TYPE_MAP =

Constants

{
  # Signed Integer Types and Aliases
  'Int8' => 21,
  'TINYINT' => 21,
  'INT1' => 21,
  'BYTE' => 21,
  'TINYINT SIGNED' => 21,
  'INT1 SIGNED' => 21,
  'Int16' => 21,
  'SMALLINT' => 21,
  'SMALLINT SIGNED' => 21,
  'Int32' => 23,
  'INT' => 23,
  'INTEGER' => 23,
  'MEDIUMINT' => 23,
  'MEDIUMINT SIGNED' => 23,
  'INT SIGNED' => 23,
  'INTEGER SIGNED' => 23,
  'Int64' => 20,
  'BIGINT' => 20,
  'SIGNED' => 20,
  'BIGINT SIGNED' => 20,
  'TIME' => 20,
  # Unsigned Integer Types and Aliases
  'UInt8' => 21,
  'TINYINT UNSIGNED' => 21,
  'INT1 UNSIGNED' => 21,
  'UInt16' => 21,
  'SMALLINT UNSIGNED' => 21,
  'UInt32' => 23,
  'MEDIUMINT UNSIGNED' => 23,
  'INT UNSIGNED' => 23,
  'INTEGER UNSIGNED' => 23,
  'UInt64' => 20,
  'UNSIGNED' => 20,
  'BIGINT UNSIGNED' => 20,
  'BIT' => 20,
  'SET' => 20,
  # Floating Point Types and Aliases
  'Float32' => 700,
  'FLOAT' => 700,
  'REAL' => 700,
  'SINGLE' => 700,
  'Float64' => 701,
  'DOUBLE' => 701,
  'DOUBLE PRECISION' => 701,
  'BFloat16' => 700,
  # Decimal Types
  'Decimal' => 1700,
  'Decimal32' => 1700,
  'Decimal64' => 1700,
  'Decimal128' => 1700,
  'Decimal256' => 1700,
  # Boolean Type
  'Bool' => 16,
  # String Types and Aliases
  'String' => 25,
  'LONGTEXT' => 25,
  'MEDIUMTEXT' => 25,
  'TINYTEXT' => 25,
  'TEXT' => 25,
  'LONGBLOB' => 17,
  'MEDIUMBLOB' => 17,
  'TINYBLOB' => 17,
  'BLOB' => 17,
  'VARCHAR' => 1043,
  'CHAR' => 1042,
  'CHAR LARGE OBJECT' => 25,
  'CHAR VARYING' => 1043,
  'CHARACTER LARGE OBJECT' => 25,
  'CHARACTER VARYING' => 1043,
  'NCHAR LARGE OBJECT' => 25,
  'NCHAR VARYING' => 1043,
  'NATIONAL CHARACTER LARGE OBJECT' => 25,
  'NATIONAL CHARACTER VARYING' => 1043,
  'NATIONAL CHAR VARYING' => 1043,
  'NATIONAL CHARACTER' => 1042,
  'NATIONAL CHAR' => 1042,
  'BINARY LARGE OBJECT' => 17,
  'BINARY VARYING' => 17,
  # Fixed String
  'FixedString' => 1042,
  # Identifier Types
  'UUID' => 2950,
  # Date and Time Types
  'Date' => 1082,
  'Date32' => 1082,
  'DateTime' => 1184,
  'DateTime64' => 1184,
  # Array Types
  'Array' => 2277,
  # JSON-like Types
  'JSON' => 3802,
  'Nested' => 3802,
  # Binary Types
  'IPv4' => 17,
  'IPv6' => 17,
  # Enum Types
  'Enum8' => 10045,
  'Enum16' => 10045,
  # Geospatial-like Types
  'Point' => 17,
  'Ring' => 17,
  'Polygon' => 17,
  # Specialized Types
  'Nothing' => 17,
  'Interval' => 1186
}.freeze

Class Method Summary collapse

Class Method Details

.connect_to_clickhouse(config) ⇒ Object 



166
167
168
169
170
171
172
173
174
175
176
 
# File 'lib/db/clickhouse.rb', line 166

def connect_to_clickhouse(config)
  # Configure ClickHouse connection with provided config
  ClickHouse.config do |config_object|
    config_object.url = config[:url]
    config_object.username = config[:username]
    config_object.password = config[:password]
  end

  # Return the connection object
  ClickHouse.connection
end

.disconnect_from_clickhouse(client) ⇒ Object 



178
179
180
 
# File 'lib/db/clickhouse.rb', line 178

def disconnect_from_clickhouse(client)
  client.close if client.respond_to?(:close)
end

.format_clickhouse_config(connection_string) ⇒ Object 



311
312
313
314
315
316
317
318
319
 
# File 'lib/db/clickhouse.rb', line 311

def format_clickhouse_config(connection_string)
  parsed = URI.parse(connection_string)
  
  {
    url: "#{parsed.scheme}://#{parsed.host}:#{parsed.port}",
    username: parsed.user || 'default',
    password: parsed.password || ''
  }
end

.get_columns_by_table_clickhouse(client, schema_name, table_name) ⇒ Object 



233
234
235
236
237
238
239
240
241
242
 
# File 'lib/db/clickhouse.rb', line 233

def get_columns_by_table_clickhouse(client, schema_name, table_name)
  sql = <<~SQL
    SELECT name as column_name 
    FROM system.columns 
    WHERE database = '#{schema_name}' AND table = '#{table_name}'
  SQL
  
  results = run_query_clickhouse(sql, client)
  results[:rows].map { |row| row['column_name'] }
end

.get_foreign_keys_clickhouse(client, schema_name, table_name, primary_key) ⇒ Object 



244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
 
# File 'lib/db/clickhouse.rb', line 244

def get_foreign_keys_clickhouse(client, schema_name, table_name, primary_key)
  depluralized_table_name = depluralize(table_name)
  
  sql = <<~SQL
    SELECT column_name 
    FROM information_schema.columns 
    WHERE table_schema = '#{schema_name}' 
    AND table_name != '#{table_name}' 
    AND (column_name = '#{primary_key}' 
      OR column_name = '#{depluralized_table_name}_#{primary_key}' 
      OR column_name = '#{depluralized_table_name}#{capitalize(primary_key)}')
  SQL

  results = run_query_clickhouse(sql, client)
  foreign_keys = results[:rows].map { |key| key['column_name'] }
  
  foreign_keys = foreign_keys.reject { |key| ['id', '_id_'].include?(key) }
  foreign_keys = foreign_keys.uniq

  if foreign_keys.empty?
    sql = <<~SQL
      SELECT column_name 
      FROM information_schema.columns 
      WHERE table_schema = '#{schema_name}' 
      AND table_name != '#{table_name}' 
      AND (column_name LIKE '#{table_name}%' 
        OR column_name LIKE '%\_id' 
        OR column_name LIKE '%Id' 
        OR column_name LIKE '%\_#{primary_key}' 
        OR column_name LIKE '%#{capitalize(primary_key)}')
    SQL

    results = run_query_clickhouse(sql, client)
    foreign_keys = results[:rows].map { |key| key['column_name'] }.uniq
  end

  foreign_keys
end

.get_schema_column_info_clickhouse(client, schema_name, table_names) ⇒ Object 



283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
 
# File 'lib/db/clickhouse.rb', line 283

def get_schema_column_info_clickhouse(client, schema_name, table_names)
  table_names.map do |table_name|
    query = <<~SQL
      SELECT 
        name as "column_name",
        type as "field_type"
      FROM system.columns
      WHERE database = '#{table_name[:schemaName]}'
      AND table = '#{table_name[:tableName]}'
    SQL

    results = run_query_clickhouse(query, client)
    {
      tableName: "#{table_name[:schemaName]}.#{table_name[:tableName]}",
      displayName: "#{table_name[:schemaName]}.#{table_name[:tableName]}",
      columns: results[:rows].map do |row|
        type_oid = parse_clickhouse_type(row['field_type'])
        {
          columnName: row['column_name'],
          displayName: row['column_name'],
          dataTypeID: type_oid,
          fieldType: row['field_type']
        }
      end
    }
  end
end

.get_schemas_clickhouse(client) ⇒ Object 



202
203
204
205
206
207
208
209
210
211
 
# File 'lib/db/clickhouse.rb', line 202

def get_schemas_clickhouse(client)
  sql = <<~SQL
    SELECT DISTINCT database AS schema_name 
    FROM system.tables 
    WHERE LOWER(database) NOT IN ('system', 'information_schema')
  SQL
  
  results = run_query_clickhouse(sql, client)
  results[:rows].map { |row| row['schema_name'] }
end

.get_tables_by_schema_clickhouse(client, schema_names) ⇒ Object 



213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
 
# File 'lib/db/clickhouse.rb', line 213

def get_tables_by_schema_clickhouse(client, schema_names)
  all_tables = schema_names.flat_map do |schema|
    sql = <<~SQL
      SELECT name as table_name, database as table_schema 
      FROM system.tables 
      WHERE database = '#{schema}'
    SQL
    
    results = run_query_clickhouse(sql, client)
    results[:rows].map do |row|
      {
        tableName: row['table_name'],
        schemaName: row['table_schema']
      }
    end
  end

  all_tables
end

.parse_clickhouse_type(type) ⇒ Object 



117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
 
# File 'lib/db/clickhouse.rb', line 117

def parse_clickhouse_type(type)
  # Remove whitespace and handle common variations
  normalized_type = type.strip.gsub(/\s+/, ' ')

  # Handle Object types
  return CLICKHOUSE_PG_TYPE_MAP['JSON'] if normalized_type.start_with?('Map(')
  return CLICKHOUSE_PG_TYPE_MAP['JSON'] if normalized_type.start_with?('AggregateFunction(')
  return CLICKHOUSE_PG_TYPE_MAP['JSON'] if normalized_type.start_with?('SimpleAggregateFunction(')

  # Handle Nullable types
  if normalized_type.start_with?('Nullable(')
    inner_type = normalized_type[9..-2]
    return parse_clickhouse_type(inner_type)
  end

  # Handle Array types
  return CLICKHOUSE_PG_TYPE_MAP['Array'] if normalized_type.start_with?('Array(')
  return CLICKHOUSE_PG_TYPE_MAP['Array'] if normalized_type.start_with?('Tuple(')

  # Handle Enum types
  return CLICKHOUSE_PG_TYPE_MAP['Enum8'] if normalized_type.start_with?('Enum8(')
  return CLICKHOUSE_PG_TYPE_MAP['Enum16'] if normalized_type.start_with?('Enum16(')

  # Handle Decimal types
  if normalized_type.match?(/^Decimal(\d*)?\(/)
    return CLICKHOUSE_PG_TYPE_MAP['Decimal']
  end

  # Handle DateTime types
  return CLICKHOUSE_PG_TYPE_MAP['DateTime'] if normalized_type.start_with?('DateTime(')
  return CLICKHOUSE_PG_TYPE_MAP['DateTime64'] if normalized_type.start_with?('DateTime64(')

  # Handle FixedString
  return CLICKHOUSE_PG_TYPE_MAP['FixedString'] if normalized_type.start_with?('FixedString(')

  # Handle LowCardinality
  if normalized_type.start_with?('LowCardinality(')
    inner_type = normalized_type[15..-2]
    return parse_clickhouse_type(inner_type)
  end

  # Direct lookup (case-insensitive)
  lookup_type = CLICKHOUSE_PG_TYPE_MAP.keys.find { |key| key.downcase == normalized_type.downcase }
  return CLICKHOUSE_PG_TYPE_MAP[lookup_type] if lookup_type

  warn "Unknown ClickHouse type: #{type}. Defaulting to VARCHAR."
  1043 # Default to Varchar
end

.run_query_clickhouse(sql, client) ⇒ Object 



182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
 
# File 'lib/db/clickhouse.rb', line 182

def run_query_clickhouse(sql, client)
  # Need to include FORMAT JSON at the end of query to include clickhouse metadata
  # Remove existing FORMAT from query, remove ending semicolon, and add FORMAT JSON
  response = response = client.execute(sql.gsub(/\s*FORMAT\s+\w+/i, '').gsub(/;\s*$/, '') + ' FORMAT JSON')

  data = response.body
  
  fields = data['meta']&.map do |field|
    {
      name: field['name'],
      dataTypeID: parse_clickhouse_type(field['type'])
    }
  end || []

  {
    fields: fields,
    rows: data['data']
  }
end