Posts Tagged ‘psql’

How Data-Pipeline’s RDS to Redshift copy template works ? (and limitations)

Written by mannem on March 3, 2016. Posted in Data Pipelines

The template contains 4 Activities.

1. RDSToS3CopyActivity – Creates a CSV file in S3 based on mySQL table.
2. RedshiftTableCreateActivity – Translates MySQL table to PSQL and creates a table(if it does not exist).
3. S3ToRedshiftCopyActivity – Runs a Redshift COPY command.
4. S3StagingCleanupActivity – Cleans up the staging S3 directory.

RedshiftTableCreateActivity is the key activity and where all the complexity lies.

It runs a shell script using ShellCommandActivity which Translates the MySQL table structure to Psql syntax , and creates a table on Redshift with translated table structure. the data-type translation between RDS and Redhsift is provided here

http://docs.aws.amazon.com/datapipeline/latest/DeveloperGuide/dp-template-redshift.html
Now, if you dig more into the ShellCommandActivity, The conversion script is downloaded as part of s3://datapipeline-us-east-1/sample-scripts/dbconv.sh , which in-turn downloads the translator python script

curl -O https://s3.amazonaws.com/datapipeline-us-east-1/sample-scripts/mysql_to_redshift.py

You can check out the contents of this script on how exactly it translates.

Ex:

mysql> create table TestTable (Id int not null , Lname varchar(20));

According to translation table , this activity , translates to a psql script , which runs on the ec2 instance.

[ec2-user@ip-172-31-1-122 ~]$ cat red0303180850.psql
-- Converted by MySql to Redshift db converter
START TRANSACTION;
 CREATE TABLE RedshiftTarget (Id int not null , Lname varchar(80));
COMMIT;

[ec2-user@ip-172-31-1-122 ~]$ cat red0303180850.psql

-- Converted by MySql to Redshift db converter

START TRANSACTION;

CREATE TABLE RedshiftTarget (Id int not null , Lname varchar(80));

COMMIT;

Make note of limitations on this script while using it !

mysql_to_redshift.py :

__author__ = 'ramaraa'

#!/usr/bin/env python

"""
Fixes a MySQL dump made with the right format so it can be
imported to a Redshift database.

Dump using:
mysqldump --compatible=postgresql --default-character-set=utf8 -r databasename.mysql -u root databasename tablename

"""

import re
import sys
import os
import time
import getopt


def file_len(filename):
    """
    Returns the equivalent of wc - l
    :param filename: file name
    :return: number of lines in the file
    """
    with open(filename) as f:
        i = 0
        for i, l in enumerate(f):
            pass
    return i + 1


def parse(input_filename, output_filename, table_name, distribution_key, redshift_sort_keys, type_map):
    # State storage
    """
    Feed it a mysqldump file, and it'll output a redshift equivalent one.
    Optional params specified here are designed for mysqldump containing only one table definition


    :rtype : void
    :param input_filename: input mysqldump file
    :param output_filename:
    :param table_name: optional. generated table name for the first table encountered, else the same as input.
    :param distribution_key: optional. distribution key column in redshift for the first table encountered.
    :param redshift_sort_keys: optional. sort key(s) column(s) in redshift for the first table encountered.
    :param type_map: optional. override type conversion from mysql to redshift.
                     tinyint(1):smallint,char(35):varchar(70),bigint(20) unsigned:bigint
    :param insert_mode: optional. https://docs.aws.amazon.com/console/datapipeline/redshiftcopyactivity.
        Determines how to handle pre-existing data in the target table that overlaps with rows in the data to be loaded.
        "allowedValues": [ "OVERWRITE_EXISTING", "KEEP_EXISTING", "TRUNCATE"]
        if insert_mode is OVERWRITE_EXISTING and distribution_key not specified, first primary key is set as dist key.
    """
    if input_filename == "-":
        num_lines = -1
    else:
        num_lines = int(file_len(input_filename))
    tables = {}
    current_table = None
    creation_lines = []
    foreign_key_lines = []
    num_inserts = 0
    started = time.time()
    table_primary_key_not_done = True

    # Open output file and write header. Logging file handle will be std out
    # unless we're writing output to std out, in which case NO PROGRESS FOR YOU.
    if output_filename == "-":
        output = sys.stdout
        logging = open(os.devnull, "w")
    else:
        output = open(output_filename, "w")
        logging = sys.stdout

    if input_filename == "-":
        input_fh = sys.stdin
    else:
        input_fh = open(input_filename)

    output.write("-- Converted by MySql to Redshift db converter\n")
    output.write("START TRANSACTION;\n")

    for i, line in enumerate(input_fh):
        time_taken = time.time() - started
        percentage_done = (i + 1) / float(num_lines)
        secs_left = (time_taken / percentage_done) - time_taken
        logging.write("\rLine %i (of %s: %.2f%%) [%s tables] [%s inserts] [ETA: %i min %i sec]" % (
            i + 1,
            num_lines,
            ((i + 1) / float(num_lines)) * 100,
            len(tables),
            num_inserts,
            secs_left // 60,
            secs_left % 60,
        ))
        logging.flush()

        line = line.decode("utf8").strip()
        # Ignore comment lines
        if line.startswith("--") or line.startswith("/*") or line.startswith("LOCK TABLES") or line.startswith(
                "DROP TABLE") or line.startswith("UNLOCK TABLES") or not line:
            continue

        # Outside of anything handling
        if current_table is None:
            # Start of a table creation statement?
            if line.startswith("CREATE TABLE"):
                # current_table is the table name in MySQL
                current_table = line.split('"')[1]
                if table_name and not table_name.isspace():
                    logging.write("\rLine %i [Encountered table %s ] [Generated table name %s]" % (
                        i + 1, current_table, table_name))
                    current_table = table_name
                    table_name = None
                tables[current_table] = {"columns": []}
                creation_lines = []
                table_primary_key_not_done = True
            # Inserting data into a table?
            elif line.startswith("INSERT INTO"):
                output.write(line.encode("utf8").replace("'0000-00-00 00:00:00'", "NULL") + "\n")
                num_inserts += 1
            # ???
            else:
                print "\n ! Ignore. Unknown line in main body: %s" % line

        # Inside-create-statement handling
        else:
            # Is it a column?
            if line.startswith('"'):
                useless, name, definition = line.strip(",").split('"', 2)
                try:
                    sql_type, extra = definition.strip().split(" ", 1)

                    # This must be a tricky enum
                    if ')' in extra:
                        sql_type, extra = definition.strip().split(")")

                except ValueError:
                    sql_type = definition.strip()
                    extra = ""

                # check if extra contains unsigned
                unsigned = "unsigned" in extra.lower()
                # remove unsigned now
                extra = re.sub("CHARACTER SET [\w\d]+\s*", "", extra.replace("unsigned", ""))
                extra = re.sub("COLLATE [\w\d]+\s*", "", extra.replace("unsigned", ""))
                extra = extra.replace("AUTO_INCREMENT", "")
                extra = extra.replace("SERIAL", "")
                extra = extra.replace("ZEROFILL", "")
                extra = extra.replace("UNSIGNED", "")
                sql_type = sql_type.lower()

                if type_map is not None and sql_type in type_map:
                    red_type = type_map[sql_type]
                elif type_map is not None and unsigned and sql_type+ " unsigned" in type_map:
                    red_type = type_map[sql_type+ " unsigned"]
                elif sql_type == "tinyint(1)":
                    red_type = "boolean"
                elif sql_type.startswith("tinyint("):
                    red_type = "smallint"
                elif sql_type.startswith("smallint("):
                    if unsigned:
                        red_type = "integer"
                    else:
                        red_type = "smallint"
                elif sql_type.startswith("mediumint("):
                    red_type = "integer"
                elif sql_type.startswith("int("):
                    if unsigned:
                        red_type = "bigint"
                    else:
                        red_type = "integer"
                elif sql_type.startswith("bigint("):
                    if unsigned:
                        red_type = "varchar(80)"
                    else:
                        red_type = "bigint"
                elif sql_type.startswith("float"):
                    red_type = "real"
                elif sql_type.startswith("double"):
                    red_type = "double precision"
                elif sql_type.startswith("decimal"):
                    # same decimal
                    red_type = sql_type
                elif sql_type.startswith("char("):
                    size = int(sql_type.split("(")[1].rstrip(")"))
                    red_type = "varchar(%s)" % (size * 4)
                elif sql_type.startswith("varchar("):
                    size = int(sql_type.split("(")[1].rstrip(")"))
                    red_type = "varchar(%s)" % (size * 4)
                elif sql_type == "longtext":
                    red_type = "varchar(max)"
                elif sql_type == "mediumtext":
                    red_type = "varchar(max)"
                elif sql_type == "tinytext":
                    red_type = "text(%s)" % (255 * 4)
                elif sql_type == "text":
                    red_type = "varchar(max)"
                elif sql_type.startswith("enum(") or sql_type.startswith("set("):
                    red_type = "varchar(%s)" % (255 * 2)
                elif sql_type == "blob":
                    red_type = "varchar(max)"
                elif sql_type == "mediumblob":
                    red_type = "varchar(max)"
                elif sql_type == "longblob":
                    red_type = "varchar(max)"
                elif sql_type == "tinyblob":
                    red_type = "varchar(255)"
                elif sql_type.startswith("binary"):
                    red_type = "varchar(255)"
                elif sql_type == "date":
                    # same
                    red_type = sql_type
                elif sql_type == "time":
                    red_type = "varchar(40)"
                elif sql_type == "datetime":
                    red_type = "timestamp"
                elif sql_type == "year":
                    red_type = "varchar(16)"
                elif sql_type == "timestamp":
                    # same
                    red_type = sql_type
                else:
                    # all else, e.g., varchar binary
                    red_type = "varchar(max)"

                # Record it
                creation_lines.append('"%s" %s %s' % (name, red_type, extra))
                tables[current_table]['columns'].append((name, red_type, extra))
            # Is it a constraint or something?
            elif line.startswith("PRIMARY KEY"):
                #composite primary key not supported in redshift
                if table_primary_key_not_done:
                    #aws datapipeline redshift copy only supports 1 primary key. remove this restriction after that is fixed
                    #creation_lines.append(line.rstrip(","))
                    first_pkey = line.rstrip(",").rstrip(")").lstrip("PRIMARY KEY").lstrip("(\"").split(",")[0].rstrip("\"")
                    pkey_line ='PRIMARY KEY("' + first_pkey + '")'
                    creation_lines.append(pkey_line)
                    if not distribution_key:
                        distribution_key = first_pkey
                    table_primary_key_not_done = False
            elif line.startswith("CONSTRAINT"):
                # Try adding foreign key in a different transaction. If it fails, no big deal.
                foreign_key_lines.append("ALTER TABLE \"%s\" ADD CONSTRAINT %s DEFERRABLE INITIALLY DEFERRED" % (
                    current_table, line.split("CONSTRAINT")[1].strip().rstrip(",")))
                # No need for index on foreign key column as Redshift does not support indexes
            elif line.startswith("UNIQUE KEY"):
                creation_lines.append("UNIQUE (%s)" % line.split("(")[1].split(")")[0])
            elif line.startswith("FULLTEXT KEY"):
                # No indexes in Redshift
                pass
            elif line.startswith("KEY"):
                pass
            # Is it the end of the table?
            elif line == ");":
                output.write("CREATE TABLE IF NOT EXISTS \"%s\" (\n" % current_table)
                for j, outline in enumerate(creation_lines):
                    output.write("    %s%s\n" % (outline, "," if j != (len(creation_lines) - 1) else ""))
                output.write(')\n')
                if distribution_key and not distribution_key.isspace():
                    output.write('distkey(%s)\n' % distribution_key)
                    distribution_key = None
                if redshift_sort_keys and not redshift_sort_keys.isspace():
                    output.write('sortkey(%s)\n' % redshift_sort_keys)
                    redshift_sort_keys = None
                output.write(';\n\n')
                current_table = None
            # ???
            else:
                print "\n ! Ignore. Unknown line inside table creation: %s" % line

    # Finish file
    output.write("COMMIT;\n")

    #output.write("START TRANSACTION;\n")
    # Write FK constraints out
    #output.write("\n-- Foreign keys --\n")
    #for line in foreign_key_lines:
    #    output.write("%s;\n" % line)
    # Finish file
    #output.write("\n")
    #output.write("COMMIT;\n")

    print ""


def usage():
    print("Usage: %s -i input -o output [-t table_name] [-d DistKey] [-s SortKey1,SortKey2...] "
          "[-m MySQL1:RedType1,MySQL2:RedType2...]" % sys.argv[0])


if __name__ == "__main__":

    input_file = ''
    output_file = ''
    gen_table_name = None
    dist_key = None
    sort_keys = None
    map_types = None
    insert_mode = None

    try:
        opts, args = getopt.getopt(sys.argv[1:], "i:o:t:d:s:m:n:",
                                   ["input_file=", "output_file=", "table_name=", "dist_key=", "sort_keys=",
                                    "map_types=", "insert_mode="])
    except getopt.GetoptError as e:
        print (str(e))
        usage()
        sys.exit(2)

    for opt, arg in opts:
        if opt in ("-i", "--input_file"):
            input_file = arg
        elif opt in ("-o", "--output_file"):
            output_file = arg
        elif opt in ("-t", "--table_name"):
            gen_table_name = arg
        elif opt in ("-d", "--dist_key"):
            dist_key = arg
        elif opt in ("-s", "--sort_keys"):
            sort_keys = arg
        elif opt in ("-m", "--map_types"):
            map_types = arg
        elif opt in ("-n", "--insert_mode"):
            insert_mode = arg

    map_types_dict = None
    if map_types and not map_types.isspace():
        map_types_dict_temp = dict([arg.split(':') for arg in map_types.lower().lstrip().split(',')])
        #sanitize keys to strip whitespaces
        map_types_dict = dict()
        for key in map_types_dict_temp:
            map_types_dict[key.lstrip().rstrip()] = map_types_dict_temp[key]

    parse(input_file, output_file, gen_table_name, dist_key, sort_keys, map_types_dict)
    sys.exit(0)

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

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

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

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

282

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

310

311

312

313

314

315

316

317

318

319

320

321

322

323

324

325

326

327

328

329

330

331

332

333

334

335

336

__author__ = 'ramaraa'

#!/usr/bin/env python

"""

Fixes a MySQL dump made with the right format so it can be

imported to a Redshift database.

Dump using:

mysqldump --compatible=postgresql --default-character-set=utf8 -r databasename.mysql -u root databasename tablename

"""

import re

import sys

import os

import time

import getopt

def file_len(filename):

"""

Returns the equivalent of wc - l

:param filename: file name

:return: number of lines in the file

"""

with open(filename) as f:

i = 0

for i, l in enumerate(f):

pass

return i + 1

def parse(input_filename, output_filename, table_name, distribution_key, redshift_sort_keys, type_map):

# State storage

"""

Feed it a mysqldump file, and it'll output a redshift equivalent one.

Optional params specified here are designed for mysqldump containing only one table definition

:rtype : void

:param input_filename: input mysqldump file

:param output_filename:

:param table_name: optional. generated table name for the first table encountered, else the same as input.

:param distribution_key: optional. distribution key column in redshift for the first table encountered.

:param redshift_sort_keys: optional. sort key(s) column(s) in redshift for the first table encountered.

:param type_map: optional. override type conversion from mysql to redshift.

tinyint(1):smallint,char(35):varchar(70),bigint(20) unsigned:bigint

:param insert_mode: optional. https://docs.aws.amazon.com/console/datapipeline/redshiftcopyactivity.

Determines how to handle pre-existing data in the target table that overlaps with rows in the data to be loaded.

"allowedValues": [ "OVERWRITE_EXISTING", "KEEP_EXISTING", "TRUNCATE"]

if insert_mode is OVERWRITE_EXISTING and distribution_key not specified, first primary key is set as dist key.

"""

if input_filename == "-":

num_lines = -1

else:

num_lines = int(file_len(input_filename))

tables = {}

current_table = None

creation_lines = []

foreign_key_lines = []

num_inserts = 0

started = time.time()

table_primary_key_not_done = True

# Open output file and write header. Logging file handle will be std out

# unless we're writing output to std out, in which case NO PROGRESS FOR YOU.

if output_filename == "-":

output = sys.stdout

logging = open(os.devnull, "w")

else:

output = open(output_filename, "w")

logging = sys.stdout

if input_filename == "-":

input_fh = sys.stdin

else:

input_fh = open(input_filename)

output.write("-- Converted by MySql to Redshift db converter\n")

output.write("START TRANSACTION;\n")

for i, line in enumerate(input_fh):

time_taken = time.time() - started

percentage_done = (i + 1) / float(num_lines)

secs_left = (time_taken / percentage_done) - time_taken

logging.write("\rLine %i (of %s: %.2f%%) [%s tables] [%s inserts] [ETA: %i min %i sec]" % (

i + 1,

num_lines,

((i + 1) / float(num_lines)) * 100,

len(tables),

num_inserts,

secs_left // 60,

secs_left % 60,

))

logging.flush()

line = line.decode("utf8").strip()

# Ignore comment lines

if line.startswith("--") or line.startswith("/*") or line.startswith("LOCK TABLES") or line.startswith(

"DROP TABLE") or line.startswith("UNLOCK TABLES") or not line:

continue

# Outside of anything handling

if current_table is None:

# Start of a table creation statement?

if line.startswith("CREATE TABLE"):

# current_table is the table name in MySQL

current_table = line.split('"')[1]

if table_name and not table_name.isspace():

logging.write("\rLine %i [Encountered table %s ] [Generated table name %s]" % (

i + 1, current_table, table_name))

current_table = table_name

table_name = None

tables[current_table] = {"columns": []}

creation_lines = []

table_primary_key_not_done = True

# Inserting data into a table?

elif line.startswith("INSERT INTO"):

output.write(line.encode("utf8").replace("'0000-00-00 00:00:00'", "NULL") + "\n")

num_inserts += 1

# ???

else:

print "\n ! Ignore. Unknown line in main body: %s" % line

# Inside-create-statement handling

else:

# Is it a column?

if line.startswith('"'):

useless, name, definition = line.strip(",").split('"', 2)

try:

sql_type, extra = definition.strip().split(" ", 1)

# This must be a tricky enum

if ')' in extra:

sql_type, extra = definition.strip().split(")")

except ValueError:

sql_type = definition.strip()

extra = ""

# check if extra contains unsigned

unsigned = "unsigned" in extra.lower()

# remove unsigned now

extra = re.sub("CHARACTER SET [\w\d]+\s*", "", extra.replace("unsigned", ""))

extra = re.sub("COLLATE [\w\d]+\s*", "", extra.replace("unsigned", ""))

extra = extra.replace("AUTO_INCREMENT", "")

extra = extra.replace("SERIAL", "")

extra = extra.replace("ZEROFILL", "")

extra = extra.replace("UNSIGNED", "")

sql_type = sql_type.lower()

if type_map is not None and sql_type in type_map:

red_type = type_map[sql_type]

elif type_map is not None and unsigned and sql_type+ " unsigned" in type_map:

red_type = type_map[sql_type+ " unsigned"]

elif sql_type == "tinyint(1)":

red_type = "boolean"

elif sql_type.startswith("tinyint("):

red_type = "smallint"

elif sql_type.startswith("smallint("):

if unsigned:

red_type = "integer"

else:

red_type = "smallint"

elif sql_type.startswith("mediumint("):

red_type = "integer"

elif sql_type.startswith("int("):

if unsigned:

red_type = "bigint"

else:

red_type = "integer"

elif sql_type.startswith("bigint("):

if unsigned:

red_type = "varchar(80)"

else:

red_type = "bigint"

elif sql_type.startswith("float"):

red_type = "real"

elif sql_type.startswith("double"):

red_type = "double precision"

elif sql_type.startswith("decimal"):

# same decimal

red_type = sql_type

elif sql_type.startswith("char("):

size = int(sql_type.split("(")[1].rstrip(")"))

red_type = "varchar(%s)" % (size * 4)

elif sql_type.startswith("varchar("):

size = int(sql_type.split("(")[1].rstrip(")"))

red_type = "varchar(%s)" % (size * 4)

elif sql_type == "longtext":

red_type = "varchar(max)"

elif sql_type == "mediumtext":

red_type = "varchar(max)"

elif sql_type == "tinytext":

red_type = "text(%s)" % (255 * 4)

elif sql_type == "text":

red_type = "varchar(max)"

elif sql_type.startswith("enum(") or sql_type.startswith("set("):

red_type = "varchar(%s)" % (255 * 2)

elif sql_type == "blob":

red_type = "varchar(max)"

elif sql_type == "mediumblob":

red_type = "varchar(max)"

elif sql_type == "longblob":

red_type = "varchar(max)"

elif sql_type == "tinyblob":

red_type = "varchar(255)"

elif sql_type.startswith("binary"):

red_type = "varchar(255)"

elif sql_type == "date":

# same

red_type = sql_type

elif sql_type == "time":

red_type = "varchar(40)"

elif sql_type == "datetime":

red_type = "timestamp"

elif sql_type == "year":

red_type = "varchar(16)"

elif sql_type == "timestamp":

# same

red_type = sql_type

else:

# all else, e.g., varchar binary

red_type = "varchar(max)"

# Record it

creation_lines.append('"%s" %s %s' % (name, red_type, extra))

tables[current_table]['columns'].append((name, red_type, extra))

# Is it a constraint or something?

elif line.startswith("PRIMARY KEY"):

#composite primary key not supported in redshift

if table_primary_key_not_done:

#aws datapipeline redshift copy only supports 1 primary key. remove this restriction after that is fixed

#creation_lines.append(line.rstrip(","))

first_pkey = line.rstrip(",").rstrip(")").lstrip("PRIMARY KEY").lstrip("(\"").split(",")[0].rstrip("\"")

pkey_line ='PRIMARY KEY("' + first_pkey + '")'

creation_lines.append(pkey_line)

if not distribution_key:

distribution_key = first_pkey

table_primary_key_not_done = False

elif line.startswith("CONSTRAINT"):

# Try adding foreign key in a different transaction. If it fails, no big deal.

foreign_key_lines.append("ALTER TABLE \"%s\" ADD CONSTRAINT %s DEFERRABLE INITIALLY DEFERRED" % (

current_table, line.split("CONSTRAINT")[1].strip().rstrip(",")))

# No need for index on foreign key column as Redshift does not support indexes

elif line.startswith("UNIQUE KEY"):

creation_lines.append("UNIQUE (%s)" % line.split("(")[1].split(")")[0])

elif line.startswith("FULLTEXT KEY"):

# No indexes in Redshift

pass

elif line.startswith("KEY"):

pass

# Is it the end of the table?

elif line == ");":

output.write("CREATE TABLE IF NOT EXISTS \"%s\" (\n" % current_table)

for j, outline in enumerate(creation_lines):

output.write(" %s%s\n" % (outline, "," if j != (len(creation_lines) - 1) else ""))

output.write(')\n')

if distribution_key and not distribution_key.isspace():

output.write('distkey(%s)\n' % distribution_key)

distribution_key = None

if redshift_sort_keys and not redshift_sort_keys.isspace():

output.write('sortkey(%s)\n' % redshift_sort_keys)

redshift_sort_keys = None

output.write(';\n\n')

current_table = None

# ???

else:

print "\n ! Ignore. Unknown line inside table creation: %s" % line

# Finish file

output.write("COMMIT;\n")

#output.write("START TRANSACTION;\n")

# Write FK constraints out

#output.write("\n-- Foreign keys --\n")

#for line in foreign_key_lines:

# output.write("%s;\n" % line)

# Finish file

#output.write("\n")

#output.write("COMMIT;\n")

print ""

def usage():

print("Usage: %s -i input -o output [-t table_name] [-d DistKey] [-s SortKey1,SortKey2...] "

"[-m MySQL1:RedType1,MySQL2:RedType2...]" % sys.argv[0])

if __name__ == "__main__":

input_file = ''

output_file = ''

gen_table_name = None

dist_key = None

sort_keys = None

map_types = None

insert_mode = None

try:

opts, args = getopt.getopt(sys.argv[1:], "i:o:t:d:s:m:n:",

["input_file=", "output_file=", "table_name=", "dist_key=", "sort_keys=",

"map_types=", "insert_mode="])

except getopt.GetoptError as e:

print (str(e))

usage()

sys.exit(2)

for opt, arg in opts:

if opt in ("-i", "--input_file"):

input_file = arg

elif opt in ("-o", "--output_file"):

output_file = arg

elif opt in ("-t", "--table_name"):

gen_table_name = arg

elif opt in ("-d", "--dist_key"):

dist_key = arg

elif opt in ("-s", "--sort_keys"):

sort_keys = arg

elif opt in ("-m", "--map_types"):

map_types = arg

elif opt in ("-n", "--insert_mode"):

insert_mode = arg

map_types_dict = None

if map_types and not map_types.isspace():

map_types_dict_temp = dict([arg.split(':') for arg in map_types.lower().lstrip().split(',')])

#sanitize keys to strip whitespaces

map_types_dict = dict()

for key in map_types_dict_temp:

map_types_dict[key.lstrip().rstrip()] = map_types_dict_temp[key]

parse(input_file, output_file, gen_table_name, dist_key, sort_keys, map_types_dict)

sys.exit(0)

Continue Reading 1 Comment

Running complex queries on redshift with Data-pipelines

Written by mannem on December 5, 2015. Posted in Data Pipelines, Redshift

Sometimes AWS Data-Pipelines SQLActivity may not support complex queries. This is because Data-Pieplines SqlActivity passes this script to JDBS executeStatement(Prepared statement). This script is supposed to be idempotent. So here’s an alternative to run psql/sql commands using Data-Pipelines.

Suppose you have the following psql command,

select 'insert into event_data_' ||to_char(current_date,'yyyymm')|| '_v2 select * from stage_event_data_v2 where event_time::date >= '''||to_char(current_date, 'YYYY-MM')||'-01'' and event_time::date <= '''||last_day(current_date)||''';';

and it should output,

insert into event_data_201511_v2 select * from stage_event_data_v2 where event_time::date >= '2015-11-01' and event_time::date <= '2015-11-30';

This is a valid command in psql and can be successfully executed with workbenches and psql shell.

But using Data-pipelines, executing the above command will throw and error:

ERROR processing query/statement. Error: Parsing failed

This is because the script appears to be changing(not idempotent) when it is executed.

If you have a complex redshift commands and wish to performing operations against Redshift that involve custom logic. You could rather write a program in your favorite language and run it
using ShellCommandActivity. This is a quite valid way of interacting with Redshift.

There are several ways to do this. I am including a shell script and its Data-pipelne template as a reference here.

Sample shell command:

#----A sample shell code to run psql queries----
#!/bin/bash -x
sudo yum install postgresql -y
sudo yum install aws-cli -y
export PGPASSWORD=$2
scriptFile=$(aws s3 ls $1 --region us-west-2 | awk '{print $4}')
aws s3 cp $1 /home/ec2-user/ --region us-west-2
psql -h redshift.rkcloud.us -p 5439 -d rkevents -U rkevents -f /home/ec2-user/$scriptFile -o /home/ec2-user/v2.sql -t
aws s3 cp /home/ec2-user/v2.sql s3://bucket/ --region us-west-2
#-------------------------------------------------

#----A sample shell code to run psql queries----

#!/bin/bash -x

sudo yum install postgresql -y

sudo yum install aws-cli -y

export PGPASSWORD=$2

scriptFile=$(aws s3 ls $1 --region us-west-2 | awk '{print $4}')

aws s3 cp $1 /home/ec2-user/ --region us-west-2

psql -h redshift.rkcloud.us -p 5439 -d rkevents -U rkevents -f /home/ec2-user/$scriptFile -o /home/ec2-user/v2.sql -t

aws s3 cp /home/ec2-user/v2.sql s3://bucket/ --region us-west-2

#-------------------------------------------------

Sample Data-pipelines template:

{
  "objects": [
    {
      "schedule": {
        "ref": "DefaultSchedule"
      },
      "instanceType": "t1.micro",
      "name": "EC2ResourceObj",
      "id": "EC2ResourceObj",
      "type": "Ec2Resource",
      "terminateAfter": "20 Minutes"
    },
    {
      "schedule": {
        "ref": "DefaultSchedule"
      },
      "scriptUri": "s3://YourBucket/shellCommands.sh",
      "name": "ShellCommandActivityObj",
      "scriptArgument": [
        "s3://YourBucket/event_data_yyyymm.sql",
        "#{*myRedshiftPass}"
      ],
      "id": "ShellCommandActivityObj",
      "runsOn": {
        "ref": "EC2ResourceObj"
      },
      "type": "ShellCommandActivity"
    },
    {
      "failureAndRerunMode": "CASCADE",
      "resourceRole": "DataPipelineDefaultResourceRole",
      "role": "DataPipelineDefaultRole",
      "pipelineLogUri": "s3://yourLogBucket/",
      "scheduleType": "cron",
      "name": "Default",
      "id": "Default"
    },
    {
      "occurrences": "1",
      "period": "1 Hour",
      "name": "MyRunOnce",
      "id": "DefaultSchedule",
      "type": "Schedule",
      "startAt": "FIRST_ACTIVATION_DATE_TIME"
    }
  ],
  "parameters": [
    {
      "description": "Redhift password",
      "id": "*myRedshiftPass"
    }
  ],
  "values": {
    "*myRedshiftPass": "MyRedshiftPass123"
  }
}

{

"objects": [

{

"schedule": {

"ref": "DefaultSchedule"

"instanceType": "t1.micro",

"name": "EC2ResourceObj",

"id": "EC2ResourceObj",

"type": "Ec2Resource",

"terminateAfter": "20 Minutes"

{

"schedule": {

"ref": "DefaultSchedule"

"scriptUri": "s3://YourBucket/shellCommands.sh",

"name": "ShellCommandActivityObj",

"scriptArgument": [

"s3://YourBucket/event_data_yyyymm.sql",

"#{*myRedshiftPass}"

"id": "ShellCommandActivityObj",

"runsOn": {

"ref": "EC2ResourceObj"

"type": "ShellCommandActivity"

{

"failureAndRerunMode": "CASCADE",

"resourceRole": "DataPipelineDefaultResourceRole",

"role": "DataPipelineDefaultRole",

"pipelineLogUri": "s3://yourLogBucket/",

"scheduleType": "cron",

"name": "Default",

"id": "Default"

{

"occurrences": "1",

"period": "1 Hour",

"name": "MyRunOnce",

"id": "DefaultSchedule",

"type": "Schedule",

"startAt": "FIRST_ACTIVATION_DATE_TIME"

}

"parameters": [

{

"description": "Redhift password",

"id": "*myRedshiftPass"

}

"values": {

"*myRedshiftPass": "MyRedshiftPass123"

}

-------------------------------------------------
Some info on the script and Data-pipeline:

1. This script file has 2 arguments (Arg 1 is the sql script that you need to execute , Arg 2 is the Redshift password). These arguments are provided in Data-pipeline shellCommandActivity object using scriptArgument field.

2. The script outputs its result to v2.sql and uploads to s3 bucket (with -t tuples only option), so that you can run the script later.

3. The Data-pipeline template uses the *myRedshiftPass parameter id to hide the password from DataPipelines.
-------------------------------------------------

Continue Reading No Comments

May 2020
M	T	W	T	F	S	S
« Jan
				1	2	3
4	5	6	7	8	9	10
11	12	13	14	15	16	17
18	19	20	21	22	23	24
25	26	27	28	29	30	31