dynamic insert statement returning an id value Yog May 7 2007 edited May 8 2007 Hi, I'm trying to create function with an insert statement that is built dynamically and executed. Dynamic query can be executed by two ways. Use ANSI dynamic SQL for LOB applications and all other new applications. How to turn off zsh save/restore session in Terminal.app. If the dynamic SQL statement is a SELECT statement that returns multiple rows, native dynamic SQL gives you these choices: Use the EXECUTE IMMEDIATE statement with the BULK COLLECT INTO clause. Statement caching can be enabled in the precompiler applications, which will help in the performance improvement of all applications that rely on the dynamic SQL statements. For example, a SELECT statement that includes an identifier that is unknown at compile time (such as a table name) or a WHERE clause in which the number of subclauses is unknown at compile time. To learn more, see our tips on writing great answers. The procedure in this example is invulnerable to SQL injection because it builds the dynamic SQL statement with bind variables (not by concatenation as in the vulnerable procedure in Example 7-16). It briefly describes the capabilities and limitations of each method, then offers guidelines for choosing the right method. In the following example, the input SQL statement contains the place-holder n: With Method 2, you must know the datatypes of input host variables at precompile time. This program uses dynamic SQL Method 2 to insert two rows into the EMP table and then delete them. Then Oracle parses the SQL statement. The OPEN statement allocates a cursor, binds input host variables, and executes the query, identifying its active set. Data definition statements usually fall into this category. LOAD_THIS:: this_date: 29-JUN-20 SQL> create table table_a (id, c_descr, c_sql) as 2 select 3, 'EMP', 'select count . With Methods 2, 3, and 4, you might need to use the statement. Dynamic queries with EXECUTE IMMEDIATE Dynamic SQL means that at the time you write (and then compile) your code, you do not have all the information you need for parsing a SQL statement. If the dynamic SQL statement does not represent an anonymous PL/SQL block or a CALL statement, repetition of placeholder names is insignificant. SQL whose text is unknown at compile time. The text is copied into the conversion result. where dbname and statementname are identifiers used by Pro*COBOL, not host or program variables. I am reviewing a very bad paper - do I have to be nice? The names of the place-holders need not match the names of the host variables. That way, you clear extraneous characters. You have 90% of what you need - seriously. "Native Dynamic SQL"for information about native dynamic SQL, Oracle Database PL/SQL Packages and Types Reference for more information about the DBMS_SQL package, including instructions for running a dynamic SQL statement that has an unknown number of input or output variables ("Method 4"). That is, Method 2 encompasses Method 1, Method 3 encompasses Methods 1 and 2, and so on. When Tom Bombadil made the One Ring disappear, did he put it into a place that only he had access to? In the USING clause of the OPEN FOR statement, specify a bind variable for each placeholder in the dynamic SQL statement. for example from output For example, the following host strings qualify: With Method 1, the SQL statement is parsed every time it is executed (regardless of whether you have set HOLD_CURSOR=YES). Oracle Database PL/SQL Packages and Types Reference for more information about DBMS_SQL.RETURN_RESULT, Oracle Call Interface Programmer's Guide for information about C and .NET support for implicit query results, SQL*Plus User's Guide and Reference for information about SQL*Plus support for implicit query results, Oracle Database Migration Guide for information about migrating subprograms that use implicit query results, Example 7-11 DBMS_SQL.RETURN_RESULT Procedure. For example, the following host strings fall into this category: With Method 2, the SQL statement can be parsed just once by calling PREPARE once, and executed many times with different values for the host variables. Typically, the user retrieves unauthorized data by changing the WHERE clause of a SELECT statement or by inserting a UNION ALL clause. PL/SQL does not create bind variables automatically when you use The use of bind descriptors with Method 4 is detailed in your host-language supplement. You can even avoid PL-SQL and can do it using a simple SQL Well - in two steps. An example using Method 2 follows: In the example, remotedb tells Oracle where to EXECUTE the SQL statement. Example 7-14 uses the DBMS_SQL.TO_CURSOR_NUMBER function to switch from native dynamic SQL to the DBMS_SQL package. Asking for help, clarification, or responding to other answers. Before passing a SQL cursor number to the DBMS_SQL.TO_REFCURSOR function, you must OPEN, PARSE, and EXECUTE it (otherwise an error occurs). The returned data could be a single column, multiple columns or expressions. This is not true when RELEASE_CURSOR=YES is also specified, because the statement has to be prepared again before each execution. Use the OPEN FOR, FETCH, and CLOSE statements. Are there anyways to create a dynamic insert statement in Oracle, or it's impossible? I have used very limited data-types in the solution (number, date and varchar2 only). Why is Noether's theorem not guaranteed by calculus? Example 7-21 Explicit Format Models Guarding Against SQL Injection. You need to be bulk-binding *something* , ie forall i in 1 .. 10 insert into t values ( l_my_array(i) ); Successful compilation creates schema object dependencies. it does not handle single quote in the text field, and serveroutput for huge table. After DBMS_SQL.RETURN_RESULT returns the result, only the recipient can access it. This is mainly incase a tester re-runs a script without backing up their data. You must also use the DBMS_SQL package if you want a stored subprogram to return a query result implicitly (not through an OUT REF CURSOR parameter). set sqlformat insert select * from t1; The output can be spooled as well: set sqlformat insert spool C:\Users\balaz\Desktop\insert.sql select * from t1; spool off Run the above as a script (F5), and not a statement (Ctrl+Enter). Total no of records in temp_tab_1 is approx 30K variables in the WHERE and VALUES clauses into bind variables (for In this example, the procedure p invokes DBMS_SQL.RETURN_RESULT without the optional to_client parameter (which is TRUE by default). Last updated: May 04, 2021 - 9:54 am UTC, Maverick, April 08, 2008 - 10:33 am UTC, Maverick, April 08, 2008 - 1:43 pm UTC, A reader, April 09, 2008 - 1:41 am UTC, Maverick, April 09, 2008 - 7:54 am UTC, A reader, April 09, 2008 - 8:45 am UTC, Maverick, April 09, 2008 - 10:07 am UTC, A reader, July 04, 2011 - 6:26 am UTC, Zahirul Haque, June 07, 2012 - 9:33 pm UTC, Zahirul Haque, August 28, 2012 - 7:42 pm UTC, Thiruppathi, September 26, 2012 - 5:39 am UTC, DIPU V P, January 15, 2013 - 8:20 am UTC, Gireesh Puthumana, May 21, 2013 - 11:18 am UTC, Ravi B, May 22, 2013 - 11:25 pm UTC, Gireesh Puthumana, May 23, 2013 - 3:56 pm UTC, Gireesh Puthumana, May 24, 2013 - 10:04 am UTC, Ravi B, May 28, 2013 - 10:42 pm UTC, Gireesh Puthumana, June 05, 2013 - 2:40 pm UTC, A reader, August 21, 2015 - 12:29 pm UTC, poshan pandey, May 03, 2021 - 6:16 pm UTC. Input (program) values are assigned to input host variables, and output (column) values are assigned to output host variables. LOBs are not supported in Oracle Method 4. That is, Oracle examines the SQL statement to make sure it follows syntax rules and refers to valid database objects. Can dialogue be put in the same paragraph as action text? You can also export the data in SQL Loader format as well. I've got this working ok. but I'd like to be able to return the id of the new record created so I can return it from my main function. For example, an input string can be a qualified SQL name (verified by DBMS_ASSERT.QUALIFIED_SQL_NAME) and still be a fraudulent password. You only get what you ask for, you never said more than two. ok, now I take it up to four tables - with overlapping sets of columns. The main argument to EXECUTE IMMEDIATE is the string containing the SQL statement to execute. DECLARE STATEMENT declares the name of a dynamic SQL statement so that the statement can be referenced by PREPARE, EXECUTE, DECLARE CURSOR, and DESCRIBE. With Methods 2 and 3, the number of place-holders for input host variables and the datatypes of the input host variables must be known at precompile time. The simplest kind of dynamic SQL statement results only in "success" or "failure" and uses no host variables. To try the examples, run these statements. The caching is only applicable for the dynamic statements and the cursor cache for the static statements co-exists with the new feature. When the stmt_cache option is used to precompile this program, the performance increases compared to a normal precompilation. Anonymous PL/SQL blocks are vulnerable to this technique. Query with unknown number of select-list items or input host variables. If it is, please let us know via a Comment. The two procedures return results in the same order. That is, any SQL construct not included in "Description of Static SQL". which improves performance. Because the SQL cursor number is a PL/SQL integer, you can pass it across call boundaries and store it. First you should build an algorithm to read those two parameter, check if both is valid SQL query, and l_query is suitable to run l_insert_query . In this example, the dynamic PL/SQL block is an anonymous PL/SQL block that invokes a subprogram that has a formal parameter of the PL/SQL collection type varray. Again, sorry about the uber long delay We ended up shoving this project to the backlog. I'm lazy so I started by reviewing your second example. A SQLDA is a host-program data structure that holds descriptions of select-list items or input host variables. That is, Oracle gets the addresses of the host variables so that it can read or write their values. With statement injection, the procedure deletes the supposedly secret record exposed in Example 7-16. Thank you so much, Alex! Example 7-18 Procedure Vulnerable to SQL Injection Through Data Type Conversion. Existence of rational points on generalized Fermat quintics, How small stars help with planet formation. DBMS_SQL.OPEN_CURSOR has an optional parameter, treat_as_client_for_results. Example 7-4 Dynamically Invoking Subprogram with Assoc. we take the number of columns that are common across all tables at the same. Continuing our example, DECLARE defines a cursor named EMPCURSOR and associates it with SQLSTMT, as follows: The identifiers SQLSTMT and EMPCURSOR are not host or program variables, but must be unique. This section describes SQL injection vulnerabilities in PL/SQL and explains how to guard against them. Therefore, DBMS_SQL.RETURN_RESULT returns the query result to the subprogram client (the anonymous block that invokes p). Always have your program validate user input to ensure that it is what is intended. In validation-checking code, the subprograms in the DBMS_ASSERT package are often useful. You did away with the temp table so it seemed simpler overall than your first example. To work around this restriction, use an uninitialized variable where you want to use NULL, as in Example 7-7. Example 7-6 Dynamically Invoking Subprogram with Varray Formal Parameter. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. Each succeeding method imposes fewer constraints on your application, but is more difficult to code. This is a first draft of the script. *Cause: now we need to create insert statement for the output and then insert that into respective tables so that we could insert that in different schema in other instance. When the number of select-list items or place-holders for input host variables is unknown until run time, your program must use a descriptor. In fact, if the dynamic SQL statement is a query, you must use Method 3 or 4. Do not null-terminate the host string. If the dynamic SQL statement is an anonymous PL/SQL block or a CALL statement, put all bind variables in the USING clause. If one of the host variables in the USING clause is an array, all must be arrays. However, some applications must accept (or build) and process a variety of SQL statements at run time. Array Formal Parameter. A generic bind SQLDA contains the following information about the input host variables in a SQL statement: Maximum number of place-holders that can be DESCRIBEd, Actual number of place-holders found by DESCRIBE, Addresses of buffers to store place-holder names, Sizes of buffers to store place-holder names, Addresses of buffers to store indicator-variable names, Sizes of buffers to store indicator-variable names, Current lengths of indicator-variable names. Thus, dynamic SQL lets you write highly flexible applications. If a program determines order of evaluation, then at the point where the program does so, its behavior is undefined. For more information about SQL cursor attributes, see "Cursors Overview". Because it holds descriptions of columns in the query select list, this structure is also called a select descriptor. Also note that dbms_output is restricted to 255 characters. you can create insert statment,through spooling. If you use dynamic SQL in your PL/SQL applications, you must check the input text to ensure that it is exactly what you expected. sandeepgupta_18 Sep 29 2022 edited Sep 29 2022. Ensure that the converted values have the format of SQL datetime or numeric literals. The command is followed by a character string (host variable or literal) containing the SQL statement to be executed, which cannot be a query. --- As a rule, use the simplest method you can. The number of select-list items, the number of place-holders for input host variables, and the datatypes of the input host variables must be known at precompile time. where emp.dept_id=dept.dept_id now this output would be containing all columns from all the tables used in query.. Bind variables can be evaluated in any order. The number of place-holders for input host variables and the datatypes of the input host variables must be known at precompile time. It then stores this information in the select descriptor. If you repeat a placeholder name, you need not repeat its corresponding bind variable. Content Discovery initiative 4/13 update: Related questions using a Machine Insert results of a stored procedure into a temporary table, Simple PL/SQL to check if table exists is not working, Nested tables: Insert values into specific columns of nested table, Oracle insert into using select to add first row and return columns without using pl/sql stored procedure, Oracle returning statement for an insert into operation with 'select from' source, How to intersect two lines that are not touching. The identifier SQLSTMT is not a host or program variable, but must be unique. Use dynamic query for this. By clicking Accept all cookies, you agree Stack Exchange can store cookies on your device and disclose information in accordance with our Cookie Policy. For example, a general-purpose report writer must build different SELECT statements for the various reports it generates. Example 7-5 Dynamically Invoking Subprogram with Nested Table Formal Parameter. Example 7-12 DBMS_SQL.GET_NEXT_RESULT Procedure. How do philosophers understand intelligence? Input host variables in the USING clause replace corresponding place-holders in the PREPAREd dynamic SQL statement. Example 7-8 Native Dynamic SQL with OPEN FOR, FETCH, and CLOSE Statements. */. Find centralized, trusted content and collaborate around the technologies you use most. The DBMS_SQL.TO_REFCURSOR function converts a SQL cursor number to a weak cursor variable, which you can use in native dynamic SQL statements. However, to write native dynamic SQL code, you must know at compile time the number and data types of the input and output variables of the dynamic SQL statement. You cannot FETCH from a PL/SQL block because it might contain any number of SQL statements. Method 4 provides maximum flexibility, but requires complex coding and a full understanding of dynamic SQL concepts. That resulted in a package that was at least syntactically valid in my tests. The command line option stmt_cache can be given any value in the range of 0 to 65535. Oracle - Insert into tables using dynamic queries, The philosopher who believes in Web Assembly, Improving the copy in the close modal and post notices - 2023 edition, New blog post from our CEO Prashanth: Community is the future of AI. For example, you know the following query returns two column values: However, if you let the user define the select list, you might not know how many column values the query will return. Since you cannot FETCH from a PL/SQL block, use Method 2 instead. I would *never* do that - it would be just about the least efficient way to move data. To subscribe to this RSS feed, copy and paste this URL into your RSS reader. rev2023.4.17.43393. It is required if you want to execute the dynamic SQL statement at a nondefault database. In our example, OPEN allocates EMPCURSOR and assigns the host variable SALARY to the WHERE clause, as follows: The FETCH statement returns a row from the active set, assigns column values in the select list to corresponding host variables in the INTO clause, and advances the cursor to the next row. If the dynamic SQL statement is a SELECT statement that can return multiple rows, put out-bind variables (defines) in the BULK COLLECT INTO clause and in-bind variables in the USING clause. The performance improvement is achieved by removing the overhead of parsing the dynamic statements on reuse. "CREATE FUNCTION Statement" for information about creating functions at schema level, "CREATE PROCEDURE Statement" for information about creating procedures at schema level, "PL/SQL Packages" for information about packages, "CREATE PACKAGE Statement" for information about declaring subprograms in packages, "CREATE PACKAGE BODY Statement" for information about declaring and defining subprograms in packages, "CREATE PACKAGE Statement" for more information about declaring types in a package specification, "EXECUTE IMMEDIATE Statement"for syntax details of the EXECUTE IMMEDIATE statement, "PL/SQL Collections and Records" for information about collection types, Example 7-1 Invoking Subprogram from Dynamic PL/SQL Block. A descriptor is an area of memory used by your program and Oracle to hold a complete description of the variables in a dynamic SQL statement. So, if the same place-holder appears two or more times in the statement after PREPARE, each appearance must correspond to a host variable in the USING clause. Dynamic SQL Statement is Not Anonymous Block or CALL Statement, Dynamic SQL Statement is Anonymous Block or CALL Statement. Advantages and Disadvantages of Dynamic SQL. Here is the code you can use. ORA-01732: data manipulation operation not legal on this view. That is, Oracle does what the SQL statement requested, such as deleting rows from a table. If the statement affects no rows, then the values of the variables are undefined. To learn more, see our tips on writing great answers. table2 is owned by Bar. I want to create an insert statement which columns can be customed. This section introduces the four methods you can use to define dynamic SQL statements. Later sections show you how to use the methods. It uses all common-across-all-tables columns in join and merges the rows which shares common values. Use the OPEN FOR, FETCH, and CLOSE statements. So, if the length of 'insert into ' exceeds 255, the query will fail. Dynamic SQL is a programming methodology for generating and running SQL statements at run time. Example 7-14 Switching from Native Dynamic SQL to DBMS_SQL Package. PROCEDURE print_number_names (x number_names); TYPE foursome IS VARRAY(4) OF VARCHAR2(5); -- Dynamic SQL statement with placeholder: -- Open cursor & specify bind variable in USING clause: -- Fetch rows from result set one at a time: OPEN c1 FOR 'SELECT * FROM TABLE(:1)' USING v1; Oracle Database PL/SQL Packages and Types Reference. The SQL statement must not be a query (SELECT statement) and must not contain any place-holders for input host variables. However, the names of database objects such as tables and columns need not be specified until run time (they cannot duplicate the names of host variables). Example 7-15 Setup for SQL Injection Examples. We are still in the process of developing the system. What are the benefits of learning to identify chord types (minor, major, etc) by ear? I am seeking an advice .. we do have 2 database instance on oracle 19c This method lets your program accept or build a dynamic SQL statement, then process it using the PREPARE and EXECUTE commands. For example, both of the following EXECUTEIMMEDIATEstatements are allowed: DECLARE The cursor declaration is local to its precompilation unit. When you embed a SQL INSERT, UPDATE, DELETE, MERGE, or SELECT Dynamically created and executed SQL statements are performance overhead, EXECUTE IMMEDIATE aims at reducing the overhead and give better performance. For more information about the DBMS_SQL.OPEN_CURSOR function, see Oracle Database PL/SQL Packages and Types Reference. Scripting on this page enhances content navigation, but does not change the content in any way. Unlike static SQL statements, dynamic SQL statements are not embedded in your source program. For information about schema object dependencies, see Oracle Database Development Guide. where HOST-VARIABLE-LIST stands for the following syntax: EXECUTE executes the parsed SQL statement, using the values supplied for each input host variable. Statement caching refers to the feature that provides and manages a cache of statements for each session. And of course, keep up to date with AskTOM via the official twitter account. Is this answer out of date? SQL data definition statements such as CREATE are executed once the PREPARE is completed. No - the insert comment is a SQL Developer/SQLcl feature. What is the etymology of the term space-time? But I did come across another project with the same problem as this one. Then, I want to open the cursor and insert into a table which column's name come from the cursor. or build the string 'select * from ' || table (being careful to avoid sql injection of course, but that is another discussion), problem comes when you fetch those values into variables. Except for multi-row queries, the dynamic string can . When a dynamic INSERT, UPDATE, or DELETEstatement has a RETURNINGclause, output bind arguments can go in the RETURNINGINTOclause or the USINGclause. ALTER SESSION SET NLS_DATE_FORMAT='DD-MON-YYYY'; ALTER SESSION SET NLS_DATE_FORMAT='"'' OR service_type=''Merger"'; Query: SELECT value FROM secret_records WHERE user_name='Anybody' AND, service_type='Anything' AND date_created>'' OR service_type='Merger'. 2,dse,200 This procedure is invulnerable to SQL injection because it converts the datetime parameter value, SYSDATE - 30, to a VARCHAR2 value explicitly, using the TO_CHAR function and a locale-independent format model (not implicitly, as in the vulnerable procedure in Example 7-18). The number of select-list items, the number of place-holders for input host variables, and the datatypes of the input host variables can be unknown until run time. To use Method 4, you set up one bind descriptor for all the input and output host variables. Share and learn SQL and PL/SQL; free access to the latest version of Oracle Database! All SQL injection techniques exploit a single vulnerability: String input is not correctly validated and is concatenated into a dynamic SQL statement. insert into t values ( 10 ); or forall i in 1 .. 10 insert into t values ( l_variable ); would not work because nothing in the insert is being bulk-bound. So, like a SQL statement, a PL/SQL block can be stored in a string host variable or literal. Every place-holder in the dynamic SQL statement after PREPARE must correspond to a host variable in the USING clause. rev2023.4.17.43393. The DBMS_SQL.RETURN_RESULT has two overloads: The rc parameter is either an open cursor variable (SYS_REFCURSOR) or the cursor number (INTEGER) of an open cursor. If you supply a select descriptor, the DESCRIBE SELECT LIST statement examines each select-list item in a prepared dynamic query to determine its name, datatype, constraints, length, scale, and precision. With all four methods, you must store the dynamic SQL statement in a character string, which must be a host variable or quoted literal. Expertise through exercise! Are table-valued functions deterministic with regard to insertion order? It does not fully work if the number or xmltype columns are null but an addition of a decode around these should do the trick. Connor and Chris don't just spend all day on AskTOM. If you repeat placeholder names in dynamic SQL statements, be aware that the way placeholders are associated with bind variables depends on the kind of dynamic SQL statement. 00000 - "SQL command not properly ended" Example 7-10 Repeated Placeholder Names in Dynamic PL/SQL Block. PL/SQL does not create bind variables automatically when you use dynamic SQL, but you can use them with dynamic SQL by specifying them explicitly (for details, see "EXECUTE IMMEDIATE Statement"). Otherwise, only one record is then processed. Apprently, the question is in the insert statement cause if I change the variable to the concrete column like name, an existing column, it works. The stmt_cache option can be set to hold the anticipated number of distinct dynamic SQL statements in the application. seems that for an install script, it would be so much easier to. Oracle Database Tutorial => Insert values in dynamic SQL Oracle Database Dynamic SQL Insert values in dynamic SQL Fastest Entity Framework Extensions Bulk Insert Bulk Delete Bulk Update Bulk Merge Example # Example below inserts value into the table from the previous example: Dynamic SQL statements can be built interactively with input from users having little or no knowledge of SQL. If the select list is unknown, the host-variable list cannot be established at precompile time by the INTO clause. Recall that for a multi-row query, you FETCH selected column values INTO a list of declared output host variables. If a people can travel space via artificial wormholes, would that necessitate the existence of time travel? This solved my problem! Instead, use C-style Comments (/* */). ----------------------------------------------. Collection types are not SQL data types. But I can't speak to the validity of the semantics. Though SQLDAs differ among host languages, a generic select SQLDA contains the following information about a query select list: Maximum number of columns that can be DESCRIBEd, Actual number of columns found by DESCRIBE, Addresses of buffers to store column values, Addresses of buffers to store column names. Because <