SnowConvert AI - Teradata - BTEQ

Translation references to convert Teradata BTEQ files to Python

Basic Teradata Query (BTEQ) is a general-purpose, command-based program that enables users on a workstation to communicate with one or more Teradata Database systems, and to format reports for both print and screen output.

In order to simulate the BTEQ functionality for Teradata in Snowflake, BTEQ files and commands are transformed to Python code, similar to the transformations performed for MultiLoad and FastLoad scripts. The generated code uses the Snowflake Python project called snowconvert.helpers which contains the required functions to simulate the BTEQ statements in Snowflake.

BTEQ Commands Translation

The following table presents the conversion for the BTEQ commands to Snowflake.

Teradata

Snowflake

Notes

ERRORCODE != 0

snowconvert.helpers.error_code != 0

.EXPORT DATA FILE=fileName

Export.report(“fileName”, “,”)

The function has no functionality

.EXPORT INDICDATA FILE=fileName

Export.report(“fileName”, “,”)

The function has no functionality

.EXPORT REPORT FILE=fileName

Export.report(“fileName”, “,”)

The function has no functionality

.EXPORT DIF FILE=fileName

Export.report(“fileName”, “,”)

The function has no functionality

.EXPORT RESET

Export.reset()

The function has no functionality

.IF ERRORCODE != 0 THEN .QUIT ERRORCODE

If snowconvert.helpers.error_code != 0: snowconvert.helpers.quit_application (snowconvert.helpers.error_code)

.IMPORT RESET

snowconvert.helpers.import_reset()

The function has no functionality

.LABEL newLabel

def NEWLABEL():
snowconvert.helpers.quit_application()

.LOGOFF

The statement is commented

.LOGON

The statement is commented

.LOGMECH

The statement is commented

.OS /fs/fs01/bin/filename.sh ‘load’

snowconvert.helpers.os(“”/fs/fs01/bin/filename.sh ‘load’ “”)

.RUN FILE=newFile

for statement in snowconvert.helpers.readrun(“newFile”): eval(statement)

.SET DEFAULTS

Export.defaults()

The function has no functionality

.SET ERRORLEVEL 3807 SEVERITY 0

snowconvert.helpers.set_error_level(3807, 0)

.SET RECORMODE OFF

Export.record_mode(False)

.SET RECORMODE ON

Export.record_mode(True)

.SET SEPARATOR ‘|’

Export.separator_string(‘|’)

The function has no functionality

.SET WIDTH 120

Export.width(120)

The function has no functionality

.Remark “”Hello world!”””

snowconvert.helpers.remark(r””””””Hello world!””””””)

.QUIT ERRORCODE

snowconvert.helpers.quit_application(

snowconvert.helpers.error_code

)

.QUIT

snowconvert.helpers.quit_application()

SQL statements

exec(statement)

$(<$INPUT_SQL_FILE)

exec_file(“$INPUT_SQL_FILE”)

= (Repeat previous command)

snowconvert.helpers.repeat_previous_sql_statement(con)

For more complicated statements presented in the previous table, subsections with more elaborated examples are explained.

.GOTO Conversion

Since we are converting BTEQ scripts to Python, certain structures that are valid in BTEQ are not inherently supported in Python. This is the case for the .GOTO command using the .Label commands.

For this reason, an alternative has been developed so that the functionality of these commands can be emulated, turning the .Label commands into functions with subsequent call statements.

Check the following code:

 .LABEL FIRSTLABEL
SELECT * FROM MyTable1;
.LABEL SECONDLABEL
SELECT * FROM MyTable2;
SELECT * FROM MyTable3;
Copy

In the example above, there were five commands. Two of them were.Labelcommands. The commandFIRSTLABELwas transformed into a function with the statement(s) that follow it below until another.LABELcommand is found. When another label is called (in this case, SECONDLABEL), that call ends the first function and starts a new one.

If we were to migrate the previous example, the result would be:

 #*** Generated code is based on the SnowConvert AI Python Helpers version 2.0.6 ***
 
import os
import sys
import snowconvert.helpers
from snowconvert.helpers import Export
from snowconvert.helpers import exec
from snowconvert.helpers import BeginLoading
con = None
def main():
  snowconvert.helpers.configure_log()
  con = snowconvert.helpers.log_on()
  FIRSTLABEL()
  snowconvert.helpers.quit_application()
def FIRSTLABEL():
  exec("""
    SELECT
      *
    FROM
      MyTable1
    """)
  SECONDLABEL()
def SECONDLABEL():
  exec("""
    SELECT
      *
    FROM
      MyTable2
    """)
  exec("""
    SELECT
      *
    FROM
      MyTable3
    """)

if __name__ == "__main__":
  main()
Copy

Notice there is a call to the functionFIRSTLABEL, this function has only one statement, which would be the only non-label command that followsFIRSTLABELin the original code. Before theFIRSTLABELfunction ends, it calls SECONDLABEL, with the statements that followed it.

  • Notes:

    • Creating a connector variable con = None, and populating it in the main() function: con = snowconvert.helpers.log_on().

    • Setting up a log: snowconvert.helpers.configure_log().

Execute Query Statements

Every SQL statement found in a BTEQ file will be executed though to theexecfunction provided by the snowconvert.helpers. Take for example the following code:

 CREATE TABLE aTable (aColumn BYTEINT);
Copy

This is converted to:

 #*** Generated code is based on the SnowConvert AI Python Helpers version 2.0.6 ***
 
import os
import sys
import snowconvert.helpers
from snowconvert.helpers import Export
from snowconvert.helpers import exec
from snowconvert.helpers import BeginLoading
con = None
def main():
  snowconvert.helpers.configure_log()
  con = snowconvert.helpers.log_on()
  exec("""
    CREATE OR REPLACE TABLE aTable (
      aColumn BYTEINT
    )
    """)
  snowconvert.helpers.quit_application()

if __name__ == "__main__":
  main()
Copy

Execute Script Files

Files that contain a user’s BTEQ commands and Teradata SQL statements are called scripts, run files, macros, or stored procedures. For example, create a file called SAMPFILE, and enter the following BTEQ script:

    .LOGON tdpid/userid,password 
   SELECT * FROM department;
   .LOGOFF
Copy

To execute the run file, enter either form of the BTEQ RUN command:

.RUN FILE=sampfile
Copy

If you convert the second code, the result is the following:

 #*** Generated code is based on the SnowConvert AI Python Helpers version 2.0.6 ***
 
import os
import sys
import snowconvert.helpers
from snowconvert.helpers import Export
from snowconvert.helpers import exec
from snowconvert.helpers import BeginLoading
con = None
def main():
  snowconvert.helpers.configure_log()
  con = snowconvert.helpers.log_on()

  for statement in snowconvert.helpers.readrun(fr"sampfile"):
    eval(statement)
  snowconvert.helpers.quit_application()

if __name__ == "__main__":
  main()
Copy

The snowconvert.helpers.readrun("sampfile") will return each line from the SAMPFILE and in theFORstatement, each one of the lines will be passed to the eval function, a method that parses the expression passed to it and runs python expression (the SAMPFILE should be converted to work) within the program.

Execute SQL Files

In some instances during the execution of a BTEQ file a SQL file can be found, take for example the SQL file called NEWSQL:

 CREATE TABLE aTable (aColumn BYTEINT);
Copy

This can be executed during a script with the following line:

 $(<$NEWSQL)
Copy

And after the conversion of the script the result is:

 #*** Generated code is based on the SnowConvert AI Python Helpers version 2.0.6 ***
 
import os
import sys
import snowconvert.helpers
from snowconvert.helpers import Export
from snowconvert.helpers import exec
from snowconvert.helpers import BeginLoading
con = None
def main():
  snowconvert.helpers.configure_log()
  con = snowconvert.helpers.log_on()
  exec("""
    CREATE OR REPLACE TABLE aTable (
      aColumn BYTEINT
    )
    """)
  snowconvert.helpers.quit_application()

if __name__ == "__main__":
  main()
Copy

The exec_file helper function will read each line from the NEWSQL file and then use the exec function as explained in the section Execute query statement.

Known Issues

No issues were found.

REPEAT

Translation specification for the REPEAT statement.

Note

Some parts in the output code are omitted for clarity reasons.

As per Teradata’s documentation, the REPEAT statement enables users to specify the maximum number of times the next SQL request is to be submitted. Note that a SQL request can be a single or multi-statement request. This is defined by the position of the semicolons for each statement following the REPEAT statement.

Syntax

REPEAT [ n [ PACK p [ REQBUFLEN b ] ] | * | RECS r]
<sql_request>
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Sample Source Patterns

With this input data:

inputData.dat

A B C
D E F
G H I
Copy
inputData2.dat
* [
] *
Copy

Teradata:

Query
 .IMPORT DATA FILE = inputData.dat;
.REPEAT *
USING var_1 (CHARACTER), var_2 (CHARACTER), var_3 (CHARACTER)
INSERT INTO testtabu (c1) VALUES (:var_1)
;INSERT INTO testtabu (c1) VALUES (:var_2) 
;INSERT INTO testtabu (c1) VALUES (:var_3) 
;UPDATE testtabu 
   SET c2 = 'X'
   WHERE c1 = :var_1 
;UPDATE testtabu 
   SET c2 = 'Y' 
   WHERE c1 = :var_2 
;UPDATE testtabu 
   SET c2 = 'Z'
   WHERE c1 = :var_3
;INSERT INTO TESTTABU (c1, c2) VALUES ('?','_');

.REPEAT 10
INSERT INTO TESTTABU2 VALUES ('John Doe', 23);

.REPEAT RECS 5
INSERT INTO TESTTABU2 VALUES ('Bob Alice', 21);

.IMPORT DATA FILE = inputData2.dat;
USING (var_1 CHARACTER, var_2 CHARACTER)
INSERT INTO testtabu (c1) VALUES (:var_1) 
;INSERT INTO testtabu (c1) VALUES (:var_2);
Copy
TESTTABU Result
C1C2
AX
DX
GX
BY
EY
HY
CZ
FZ
IZ
?_
?_
?_
*null
[null
TESTTABU2 Result
MY_NAMEMY_AGE
John Doe23
John Doe23
John Doe23
John Doe23
John Doe23
John Doe23
John Doe23
John Doe23
John Doe23
John Doe23
Bob Alice21
Bob Alice21
Bob Alice21
Bob Alice21
Bob Alice21

Snowflake:

Query
 #*** Generated code is based on the SnowConvert AI Python Helpers version 2.0.6 ***
 
import os
import sys
import snowconvert.helpers
from snowconvert.helpers import Export
from snowconvert.helpers import exec
from snowconvert.helpers import BeginLoading
con = None
def main():
  snowconvert.helpers.configure_log()
  con = snowconvert.helpers.log_on()
  snowconvert.helpers.import_file(fr"inputData.dat")
  ssc_repeat_value = '*'
  ssc_max_iterations = 1

  for ssc_repeat_position in range(0, ssc_max_iterations):

    if ssc_repeat_position == 0:
      using = snowconvert.helpers.using("var_1", "CHARACTER", "var_2", "CHARACTER", "var_3", "CHARACTER", rows_to_read = ssc_repeat_value)
      exec("""
        INSERT INTO testtabu (c1)
        VALUES (:var_1)
        """, using = using)
      exec("""
        INSERT INTO testtabu (c1)
        VALUES (:var_2)
        """, using = using)
      exec("""
        INSERT INTO testtabu (c1)
        VALUES (:var_3)
        """, using = using)
      exec("""
        UPDATE testtabu
          SET
            c2 = 'X'
          WHERE
            c1 = :var_1
        """, using = using)
      exec("""
        UPDATE testtabu
          SET
            c2 = 'Y'
          WHERE
            c1 = :var_2
        """, using = using)
      exec("""
        UPDATE testtabu
          SET
            c2 = 'Z'
          WHERE
            c1 = :var_3
        """, using = using)
      exec("""
        INSERT INTO TESTTABU (c1, c2)
        VALUES ('?', '_')
        """, using = using)

  ssc_repeat_value = 10
  ssc_max_iterations = 10

  for ssc_repeat_position in range(0, ssc_max_iterations):
    exec("""
      INSERT INTO TESTTABU2
      VALUES ('John Doe', 23)
      """)
  ssc_repeat_value = 5
  ssc_max_iterations = 5

  for ssc_repeat_position in range(0, ssc_max_iterations):
    exec("""
      INSERT INTO TESTTABU2
      VALUES ('Bob Alice', 21)
      """)
  snowconvert.helpers.import_file(fr"inputData2.dat")
  using = snowconvert.helpers.using("var_1", "CHARACTER", "var_2", "CHARACTER", rows_to_read = 1)
  exec("""
    INSERT INTO testtabu (c1)
    VALUES (:var_1)
    """, using = using)
  exec("""
    INSERT INTO testtabu (c1)
    VALUES (:var_2)
    """, using = using)
  snowconvert.helpers.quit_application()

if __name__ == "__main__":
  main()
Copy
TESTTABU Result
C1C2
AX
DX
GX
BY
EY
HY
CZ
FZ
IZ
?_
?_
?_
*null
[null
TESTTABU2 Result
MY_NAMEMY_AGE
John Doe23
John Doe23
John Doe23
John Doe23
John Doe23
John Doe23
John Doe23
John Doe23
John Doe23
John Doe23
Bob Alice21
Bob Alice21
Bob Alice21
Bob Alice21
Bob Alice21

Known Issues

No issues were found.

Related EWIs

No related EWIs.

USING REQUEST MODIFIER

Translation specification for the USING REQUEST MODIFIER query.

Note

Some parts in the output code are omitted for clarity reasons.

As per Teradata’s documentation, the USING REQUEST MODIFIER defines one or more variable parameter names to be used in the subsequent SELECT, INSERT, UPDATE, or DELETE statements to import or export data.

The syntax for this statement is as follows:

 USING ( <using_spec> [,...] ) SQL_request

<using_spec> ::= using_variable_name data_type [ data_type_attribute [...] ]
  [ AS { DEFERRED [BY NAME] | LOCATOR } ]
Copy

As stated in Teradata’s documentation, the USING REQUEST MODIFIER needs to be preceded by an .IMPORT statement for it to load the data into the defined parameters.

Thus, the transformation for this statement follows these steps:

  1. Call the import_file() function from the SnowConvert AI Helpers. This loads the data into a temporary file.

  2. Call the using() function from the SnowConvert AI Helpers to create a dictionary with the loaded data.

  3. For each query, run the exec() function from the SnowConvert AI Helpers and pass the previously defined dictionary. This will use Snowflake Python Connector data binding capabilities.

With this input data:

 A,B,C
Copy

Teradata (MultiLoad)

Query

 .IMPORT DATA FILE = inputData.dat;
USING var_1 (CHARACTER), var_2 (CHARACTER), var_3 (CHARACTER)
INSERT INTO testtabu (c1) VALUES (:var_1)
;INSERT INTO testtabu (c1) VALUES (:var_2) 
;INSERT INTO testtabu (c1) VALUES (:var_3) 
;UPDATE testtabu 
   SET c2 = 'X'
   WHERE c1 = :var_1 
;UPDATE testtabu 
   SET c2 = 'Y' 
   WHERE c1 = :var_2 
;UPDATE testtabu 
   SET c2 = 'Z'
   WHERE c1 = :var_3;
Copy

Result

ROWC1C2
1AX
2BY
3CZ

Snowflake (Python)

Query
 #*** Generated code is based on the SnowConvert AI Python Helpers version 2.0.6 ***
 
import os
import sys
import snowconvert.helpers
from snowconvert.helpers import Export
from snowconvert.helpers import exec
from snowconvert.helpers import BeginLoading
con = None
def main():
  snowconvert.helpers.configure_log()
  con = snowconvert.helpers.log_on()
  snowconvert.helpers.import_file(fr"inputData.dat")
  using = snowconvert.helpers.using("var_1", "CHARACTER", "var_2", "CHARACTER", "var_3", "CHARACTER", rows_to_read = 1)
  exec("""
    INSERT INTO testtabu (c1)
    VALUES (:var_1)
    """, using = using)
  exec("""
    INSERT INTO testtabu (c1)
    VALUES (:var_2)
    """, using = using)
  exec("""
    INSERT INTO testtabu (c1)
    VALUES (:var_3)
    """, using = using)
  exec("""
    UPDATE testtabu
      SET
        c2 = 'X'
      WHERE
        c1 = :var_1
    """, using = using)
  exec("""
    UPDATE testtabu
      SET
        c2 = 'Y'
      WHERE
        c1 = :var_2
    """, using = using)
  exec("""
    UPDATE testtabu
      SET
        c2 = 'Z'
      WHERE
        c1 = :var_3
    """, using = using)
  snowconvert.helpers.quit_application()

if __name__ == "__main__":
  main()
Copy
Result
ROWC1C2
1AX
2BY
3CZ

Known Issues

1. .REPEAT command is not yet supported

The .REPEAT command is not yet supported. This means that the USING REQUEST MODIFIER will only use the data loaded from the first row of the input file. Thus, the queries will only run once.

This issue should be fixed when the .REPEAT command receives proper transformation support.

If you have any additional questions regarding this documentation, you can email us at snowconvert-support@snowflake.com.

Related EWIs

No related EWIs.

Language: English