Switching to SQL File Definitions from DDS

Transcription

1 Switching to SQL File Definitions from DDS SQL uery for IBM i with Bob Cozzi bob@coztools.com 2017 Cozzi Productions, Inc. Excel, JSON & more with SQL

2 Download this Presentation Excel and JSON using SQL

3 SQL uery Powerful Database Query and SQL Scripting for IBM i Cozzi Productions, Inc. www. Web or Command Line SQL processor Powerful Scripting Tool "SiLQ" Supports IBM i DB2 SQL Run any SQL command Send SQL SELECT results to your choice of output formats CSV, Sylk, JSON, Excel, XML, PDF, Print, Display, etc. Excel and JSON using SQL

4 SQL uery SQL Processing and Scripting for IBM i Your Data Your Data with SQL uery TXT {JSON} CSV, * Write One and Done! Results are blah 2016 Cozzi Productions, Inc. Excel and JSON using SQL

5 Classic IBM i DDS File Definition Record Format Name Column (Field) Names Column Headings and Text Primary Key Fields

6 DDS Method for Creating or Maintaining Files CRTPF Create Physical File CRTPF FILE(CUSTMAST) SRCFILE(COZTEST/QDDSSRC) SRCMBR(CUSTMAST) CHGPF Change Physical File Add/Remove fields Add/Remove key fields Change column text File Properties Size, attributes etc. Data is preserved where possible CHGPF FILE(CUSTMAST) SRCFILE(COZTEST/QDDSSRC) SRCMBR(CUSTMAST) Excel and JSON using SQL

7 Change Physical File (CHGPF) Command

8 SQL for i DDL Table (File) Definition Excel and JSON using SQL

9 Basic Differences Between DDS vs DDL DDS is Keyword oriented One line or statement per field definition All field attributes are added via different keywords to the same statement SQL DDL is Statement, Keyword, Clause, Value oriented Column definitions are one statement Additional column attribute are added through additional statements Excel and JSON using SQL

10 Justifying Transforming DDS into SQL DDL IBM has "frozen" DDS No longer being updated it, except fixes SQL's Data Definition Language DDL is the new database definition standard New features in the database Only being implemented in SQL DDL NOT being added to legacy DDS e.g., auto-increment fields Default Values Display File DDS however is still being updated But it is largely unrelated to Database DDS except for syntax Excel and JSON using SQL

11 Transforming DDS into SQL DDL SQL uses DDL (Data Definition Language) to define things More lines of code to accomplish same thing as DDS, but it's worth it CREATE TABLE LABEL ON (to add text and column headings) Three methods exist to transform DDS to DDL 1. Manually write the DDL 2. Use the QSQGNDDL API or the SQL uery RTVSQLSRC 3. Use the Db2 for i SQL GENERATE_SQL() Procedure Excel and JSON using SQL

12 Generating SQL DDL from Existing Files The QSQGNDDL API is a good choice The SQL uery RTVSQLSRC command is easier The GENERATE_SQL() procedure is pervasive not too complex On everyone's system Has a complex parameter list, but it is learnable Excel and JSON using SQL

13 SQL uery RTVSQLSRC Command

14 SQL for IBM i Services Procedure RTVSQLSRC uses QSQGNDDL API to extract the file's definition A good alternative is the IBM-supplied SQL Procedure QSYS2.GENERATE_SQL() CALL QSYS2.GENERATE_SQL( File-name, Library, SQL-Object-type, Source-file, Source-library, Source member, Options... ) Must be run via an SQL Processor Excel and JSON using SQL

15 Running the GENERATE_SQL Procedure Must be run from an SQL processor Embedded in RPG RUNSQL IBM's hijacked "Run an SQL Statement" Command RUNSQLSTM IBM's Run SQL/PL Script RUNRY SQL uery Run SQL Statements or SQL and SiLQ Scripts STRSQL Interactive SQL (the old Green Screen SQL environment) RUN SQL Scripts which is part of Access Client Solutions (ACS) Previously the Client Access product You have lots of choices

16 GENERATE_SQL Example CALL QSYS2.GENERATE_SQL( 'CUSTMAST', 'COZTEST', 'TABLE', 'QSQLSRC', 'COZTEST', 'CUSTMAST', File Name Library SQL Type Source File Source Library Source Member STATEMENT_FORMATTING_OPTION => '0' ) The STATEMENT_FORMAT_OPTION option is essentially a required parameter. Without it, the source file contains extra EOL characters and ruins the source member.. Excel and JSON using SQL

17 STATEMENT_FORMATTING_OPTION => '0' From the IBM Website: formatting-option The formatting option used in the generated SQL statements. The valid values are: 0 - No additional formatting characters are added to the generated SQL statements. 1 - Additional end-of-line characters and tab characters are added to the generated SQL statements. If formatting-option is not specified, 1 will be used. Always specify '0' or you will not be happy.

18 Generating DDL from Existing File The CUSTMAST File (show earlier) Exists Need to migrate the file to DDL statements CREATE or REPLACE TABLE LABEL ON TABLE LABEL ON COLUMN "IS" for Column Headings LABLE ON COLUMN "TEXT IS" for Column Text Descriptions CREATE INDEX may also be generated for key fields May want to use PRIMARY KEY instead To generate the SQL DDL call the GENERATE_SQL() Procedure

19 GENERATE_SQL Example CALL QSYS2.GENERATE_SQL( 'CUSTMAST', 'COZTEST' 'TABLE', 'QSQLSRC', 'COZTEST', 'CUSTMAST', Replace Source Member Generate "Create or Replace" statement STATEMENT_FORMATTING_OPTION => '0', REPLACE_OPTION => '1', CREATE_OR_REPLACE_OPTION=>'1' ) Excel and JSON using SQL

20 Generated SQL from RTVSQLSRC or GENERATE_SQL File Name CREATE or REPLACE TABLE If table doesn't exist Table is Created Field ("column") If table exists Names Table definition is altered Data is preserved Record Format Name

21 Comparing DDS to SQL DDL CREATE INDEX COZTEST.CUSTMAST_QSQGNDDL_00001? ON COZTEST.CUSTMAST ( CUSTNO ASC ) ;

22 Key Fields in SQL DDL Manual Step? PRIMARY KEY (CUSTNO) Key Fields "Primary Key"

23 Remainder of DDL Table Definition Source File Text Column Headings Column Text Descriptions

24 Using RUNRY to Create or Replace TABLE RUNRY SRCMBR(CUSTMAST) SRCFILE(COZTEST/QSQLSRC) Type command, press Enter. ===> RUNRY SRCMBR(CUSTMAST) SRCFILE(COZTEST/QSQLSRC)_ Table CUSTMAST in COZTEST created but was not journaled. : Returned SQLState: SQLCode: 7905 from execsql RC(1) The CUSTMAST Table is created in COZTEST The file was not journaled so SQLSTATE '01567' is returned This can be ignored Note: RUNRY defaults to COMMIT(*NONE)

25 Using RUNSQLSTM to Create or Replace TABLE RUNSQLSTM SRCMBR(CUSTMAST) SRCFILE(COZTEST/QSQLSRC) COMMIT(*NONE) Type command, press Enter. ===> RUNSQLSTM SRCMBR(CUSTMAST) SRCFILE(COZTEST/QSQLSRC)_COMMIT(*NONE) Table CUSTMAST in COZTEST created but was not journaled. The CUSTMAST Table is created in COZTEST The file was not journaled This can be ignored

26 SQL uery Script vs RUNSQLSTM SQL uery SiLQ (Scripting Language) Provides dynamic creation of SQL statements at runtime Session Variables Can be used a substitution values in the SQL statements Can be used as target of SELECT INTO Conditional Logic Conditioning which statements are run Conditioning what parts of a (for example) SELECT statement are included Looping FOREACH Loop until End of File (uses a SELECT statement) FOR (or DO) Similar to RPG's "FOR" opcode. FOR &I = 1 to 10 by 1; WHILE Loop: Classic DO WHILE Built-in opcodes and symbolic names for hard to reach information System Values, System Name, etc. SQL/PL (Procedure Language) Create UDF, UDTF and Procedures "Compiles" SQL Functions Run completed SQL statements Can use ACS RUN SQL Script for some scripts, but RUNSQLSTM still the "go to" command for SQL Function/Procedure/Table Creation. Bottom line, both RUNRY and RUNSQSTM are needed for a complete SQL Development Environment

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