Messing with SQL in Dataflex What is available in Dataflex 19.0 o cconnection.pkg

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1 Messing with SQL in Dataflex What is available in Dataflex 19.0 ccnnectin.pkg Lts f useful stuff in there. Will take sme time t srt. DataDict.pkg Sme calls in the dd fr SQL It has a helper class. Des a few things needed fr DD I came in truble when creating filters with dates r datetime Yu cannt just cnstrain with the DF date in SQL filters. Needs t be cnverted t SQL frmat Sql.pkg Lts f stuff and has DFDate t SQL and vs cnversins Cli.pkg Lt f definitins lwer level Als, the DFDate sql Data Cnversins, but in this case als dealing with null dates DbSuggestinFrm.pkg Actually, it is WinSuggestin.pkg uses the SQL filters Can be used as Sample t lk at. Samples Stred prcedure sample is frm the ld days. Sample in StredPrcedureMSSQL.vw in the Specialized Cmpnents #Replace CS_CONNECT "SERVER=(lcal);Trusted_Cnnectin=yes;Database=Order" //*** The SQL handle manager bject Object SQLHandler Is A csqlhandlemanager Mve Self T hsql End_Object // SQLHandler Des nt use the new ccnnectin class. The Dataflex install des nt deply a sample wrking with MSSQL database Maybe I am wrng but yu are very much n yur wn. SQL Stuff t give sme attentin. (lk in cde library frum) Raveen Ryan Sundram SQL Functins fr DataFlex Cnnectivity Kits (2012) Nice stuff but A lt has been added t the df drivers since. Written fr DB2. Matt Davidian SQL Lab (2014) Take a lk, run it and lk at the cde generated.

2 SQL - Structured Query Language Readability???, well readability f SQL is nt always as great, fr sure if the statement gets bigger and mre aliases are used, fr sure if ne letter alias name srt f randmly picked r nt just use a, b, c, d, e, f,... D nt knw why that is needed with current aut cmplete editr. But maybe yu can call yurself at that mment a die-hard SQL prgrammer. Yes, I did mess arund with SQL wh remembers FlexQL? in Btrieve t speed stuff up, created a that time sme classes. Mainly t remve all the recurring cde t cnnect and discnnect. In general, I d nt knw SQL that well, can d queries and when I need smething I srt it ut. Df applicatin released in a full windw versin in 1998 Time and Attendance, Human Resurce and Payrll. Incremental updates ver time. And many f thse updates because the gvernment decided smething needed t be changed. [Read we need mre mney s we are ging t change the tax rules] Even nicer if they d it retr. Using databases fr each cmpany. S, the user had t have multiple applicatins pen at the same time if she wanted t wrk in mre the ne cmpany Because f the multiple databases maintenance tables had t be kept up t date in all thse databases. Was using the embedded database.

3 But Needed a bigger update. Started lng ag. On several areas, like the cjgrid, cjmenu, but never ended in a final release. Old dbgrid, limited filter pssibilities, had several peratr rights limitatins but was cded as Cnstraint AS. What t use fr database. Stay with embedded? Than the need t update... What t add. Request fr multiple cmpanies in ne database. Multi Currency Applicatin fr payrll We wrk in the Caribbean and have t deal with multiple cuntries s multiple tax regimes and by that the lcal tax currency. But the head cmpany wants cnslidatin reprts in ne currency Give mre features by having them all in ne app. Reprting Rewrite majr parts f the system Cde was way t ld, very hard t maintain. Many limitatins.

4 And after 25 years it is needed. Clean cde and prper File and field names we have a bigger length nw is it nt? Questin t cnference rm, wh has all the right and perfect naming fr tables and fields? Think there was ne finger. When wrking n a new release I change any name which is nt a 100% clear t me anymre. Cmpile and fix the incrrect field name errrs. Just d that during the whle develping. At cnversin time I deal with it. I d keep crss reference list. Add Webservices fr additinal functinality. What t d with the database. Stay with embedded. Lest be hnest that is very end f life. Mve t SQL? Nice fr new sales. Mre credibility and all the ther cmmn arguments. But fr current users. D they want t frk ut mre fr the same functinality? Embedded is wrking is it nt? Why buy SQL server, cst fr a License if express is nt enugh? What is there t gain? Cst vs Extra S, start t use SQL within Dataflex t make use f the backend. Use filters t d security when nt all users are allwed t wrk in all cmpanies. Use filters in prcesses t speed up where indexes are limited. Set_Attribute DF_FILE_SQL_FILTER f (RefTable (Emp_Head)) t ssql_where Set_Attribute DF_FILE_SQL_FILTER_ACTIVE f (RefTable (Emp_Head)) t True Clear Emp_Head Find Ge Emp_Head by Index.1 Reprting by using SQL view. We have Transactinal and histry tables Reprting is harder t shw infrmatin frm bth and slw, reads way t many recrds. Make use f Blbs in SQL fr requested security f files and the dcuments the system creates. Mve vtxtext t ucfile Reread Merge Set_Field_Value (RefTable (Merge)) (RefTable (Merge.Dcument)) t ucfile SaveRecrd Merge Unlck Embedded SQL t give mre features and mre speed.

5 Example: Same view as abve but nw a cjgrid which get filled by SQL On the right there is a dcking view where end users can make all kind f selectins t dynamic limit data shwn

6 It is clear that this will nt be an ptimizable selectin fr indexes. But SQL has n prblem with that, and is fast t perfrm the query. S, mre features fr the end user. Hw t d embedded SQL? Cde wise String ssql Mve (ssql * SELECT "Skl_Tble"."Descriptin", Mve (ssql * "Skl_Tble"."Skl_Tble_ID" Mve (ssql * FROM "Skl_Tble" Mve (ssql * WHERE "Skl_Tble"."Drpped" = 'N' Mve (ssql * ORDER BY "Skl_Tble"."Descriptin" ) t ssql ) t ssql ) t ssql ) t ssql ) t ssql Shuld be: Mve (ssql * WHERE "Skl_Tble"."Drpped" = + 'N' ) t ssql Pretty hard readable and maintainable. Well the sample is in fact pretty k. Only the yellw will n wrk t well. Resurces r the use f the ld images. Did read n the newsgrup t wrk that way. Hw much different is that frm the abve? Read them in Read the SQL file in and make the call? A bit risky smene can change the SQL cde Stred prcedures Nice but then if yu have t wrk against anther SQL engine, yu will have t cde it there t. And then the always changing file and field names, yes maybe a bad habit, yu shuld nt d that in SQL but I stick t it

7 S hw abut the fllwing cde: Prcedure InitializeGrid tdatasurcerw[] stdatasurcerws Handle hsql_resultset Get Create (RefClass (HRp_cSql_ResultSet)) t hsql_resultset Send dadd_select_filefield f hsql_resultset (RefTable (Skl_Tble)) (RefTable Skl_Tble.Descriptin)) Send dadd_select_filefield f hsql_resultset (RefTable (Skl_Tble)) (RefTable Skl_Tble.Skl_Tble_ID)) Send dadd_frmfile f hsql_resultset (RefTable (Skl_Tble)) Send dadd_where f hsql_resultset (RefTable (Skl_Tble)) ; (RefTable (Skl_Tble.Drpped)) ; False ; c_select_eq ; "N" ; "" Send dadd_order_by f hsql_resultset (RefTable (Skl_Tble)) (RefTable (Skl_Tble.Descriptin)) Get givedatasurcerws f hsql_resultset t stdatasurcerws Send Destry f hsql_resultset Send InitializeData stdatasurcerws End_Prcedure If naming f files and fields are changing, this way it gives a cmpiler errr Fairly easy readable, maintainable, easy extendable cde Creates a tdatasurce fr me. Deals hidden in the class autmatically with all the cnversins needed, like DateTime and Date fields. The SQL result cannt be used directly t fill the grids. Yes it des Jins t. Des it d all? N way, there is s much pssible in SQL but every time I need smething new, I just add it. At the mment it des what I need. It creates ne-line lng SQL string statement and I use: T frmat it prperly fr pssible use in the SQL Management Studi.

8 Other SQL stuff Cpy recrds Get Create (RefClass (HRp_cSQL_Cpy_Recrds)) t hcpy_recrds Set pitable_frm f hcpy_recrds t Ded_Tran.File_Number Set pitable_t f hcpy_recrds t Ded_Hist.File_Number Send dadd_where f hcpy_recrds (RefTable (Ded_Tran)) ; (RefTable (Ded_Tran.Cmpany_ID)) ; False ; c_select_eq ; GLBS_CmpanyPayrll ; "" Send dadd_where f hcpy_recrds (RefTable (Ded_Tran)) ; (RefTable (Ded_Tran.Emp_Head_ID)) ; False ; c_select_eq ; semp_head_id ; "" Send dprcesscpy f hcpy_recrds Send Destry f hcpy_recrds Delete recrds Send dsql_deleterecrds_multi_where stsql_wheres Bth calls are perfrming very fast in the SQL engine

9 Cnversin. Needed t cmbine multiple databases in t ne Renaming f many table and field names. Als, many functinality changes, additins, remve f nt used fields Remve f utdated histric garbage infrmatin in fields, s cnversin f data At first cpy data ver recrd by recrd frm Dataflex t SQL table. Way t slw Nw exprting t a CSV file. Then use the SQL imprt called Bulk Insert. Bulk insert [db].[my_table] frm 'c:\data\imprt\my_csv_file.csv' With (FIELDTERMINATOR = ' ', ROWTERMINATOR = '\n') This is blazing fast. Wrked with Dave Rbinsn during the cnference n an imprt which tk hurs by using dbimprt t a few minutes with the bulk insert After the imprt data gets checked by a utility I wrte in the begin stages when the applicatin was mved frm ds t windws. Validates every recrd every field thrugh the datadictinairy.

10 Future with messing with SQL. Well first finish SQL in memry Temp tables feature f SQL 2016 and up if I am crrect. Use cnnectin ID t switch databases, nt needed at the mment fr first release. Reprting nly with SQL statements Further speed ptimizatins. Mre nice ptins. Summarizing It is harder t push current embedded custmer t SQL database withut giving mre advantages. SQL can be used t speed up prcesses Use SQL Filters. (n file and in dd s) Use SQL calls fr delete and cpy recrds Use Bulk Insert fr yu wn stuff SQL filters can be used in dd s in yur views t d mre. Reprting Views SQL query Give mre features t yur custmers by using SQL calls. But again, yu are n yur wn. Vdf 19.0 des nt give yu t much help. Peter van Wijk phvwijk@x-rganize.cm