I have column: "LASTTOUCH" TIMESTAMP(9) NOT NULL ENABLE and I must set current date to this column. But I have no idea how I can do it. Could you help me, please? 100 DBMS_SQL. The DBMS_SQL package provides an interface to use dynamic SQL to parse any data manipulation language (DML) or data definition language (DDL) statement. · If you want to store date and time information in Oracle, you really only have two different options for the column's datatype. Lets take a quick look at. ![]() ![]() A Comparison of Oracle's DATE and TIMESTAMP Datatypes — Database. Journal. com. If you want to store date and time information in Oracle, you really only have two different options for the column's datatype. Lets take a quick look at these two datatypes and what they offer. DATE datatype. This is the datatype that we are all too familiar with when we think about representing date and time values. It has the ability to store the month, day, year, century, hours, minutes, and seconds. ![]() It is typically good for representing data for when something has happened or should happen in the future. The problem with the DATE datatype is its' granularity when trying to determine a time interval between two events when the events happen within a second of each other. This issue is solved later in this article when we discuss the TIMESTAMP datatype. In order to represent the date stored in a more readable format, the TO_CHAR function has traditionally been wrapped around the date as in Listing A. LISTING A: Formatting a date. SQL> SELECT TO_CHAR(date. MM/DD/YYYY HH2. 4: MI: SS') "Date" FROM date_table. About the only trouble I have seen people get into when using the DATE datatype is doing arithmetic on the column in order to figure out the number of years, weeks, days, hours, and seconds between two dates. What needs to be realized when doing the calculation is that when you do subtraction between dates, you get a number that represents the number of days. You should then multiply that number by the number of seconds in a day (8. Check out Listing B for my solution on how to extract the individual time intervals for a subtraction of two dates. I am aware that the fractions could be reduced but I wanted to show all the numbers to emphasize the calculation. LISTING B: Determine the interval breakdown between two dates for a DATE datatype 1 SELECT TO_CHAR(date. MMDDYYYY: HH2. 4: MI: SS') date. TO_CHAR(date. 2,'MMDDYYYY: HH2. MI: SS') date. 2. FROM date_table. DATE1 DATE2 SECONDS MINUTES HOURS DAYS WEEKS. TIMESTAMP datatype. One of the main problems with the DATE datatype was its' inability to be granular enough to determine which event might have happened first in relation to another event. Oracle has expanded on the DATE datatype and has given us the TIMESTAMP datatype which stores all the information that the DATE datatype stores, but also includes fractional seconds. If you want to convert a DATE datatype to a TIMESTAMP datatype format, just use the CAST function as I do in Listing C. As you can see, there is a fractional seconds part of '. This is only because when converting from the DATE datatype that does not have the fractional seconds it defaults to zeros and the display is defaulted to the default timestamp format (NLS_TIMESTAMP_FORMAT). If you are moving a DATE datatype column from one table to a TIMESTAMP datatype column of another table, all you need to do is a straight INSERTSELECT FROM and Oracle will do the conversion for you. Look at Listing D for a formatting of the new TIMESTAMP datatype where everything is the same as formatting the DATE datatype as we did in Listing A. Beware while the TO_CHAR function works with both datatypes, the TRUNC function will not work with a datatype of TIMESTAMP. This is a clear indication that the use of TIMESTAMP datatype should explicitly be used for date and times where a difference in time is of utmost importance, such that Oracle won't even let you compare like values. If you wanted to show the fractional seconds within a TIMESTAMP datatype, look at Listing E. In Listing E, we are only showing 3 place holders for the fractional seconds. LISTING C: Convert DATE datatype to TIMESTAMP datatype. SQL> SELECT CAST(date. AS TIMESTAMP) "Date" FROM t. JUN- 0. 3 0. 4. 5. PM. 2. 6- JUN- 0. AM. LISTING D: Formatting of the TIMESTAMP datatype 1 SELECT TO_CHAR(time. MM/DD/YYYY HH2. 4: MI: SS') "Date" FROM date_table. LISTING E: Formatting of the TIMESTAMP datatype with fractional seconds 1 SELECT TO_CHAR(time. MM/DD/YYYY HH2. 4: MI: SS: FF3') "Date" FROM date_table. Calculating the time difference between two TIMESTAMP datatypes is much easier than the old DATE datatype. Look at what happens when you just do straight subtraction of the columns in Listing F. As you can see, the results are much easier to recognize, 1. This means no more worries about how many seconds in a day and all those cumbersome calculations. And therefore the calculations for getting the weeks, days, hours, minutes, and seconds becomes a matter of picking out the number by using the SUBSTR function as can be seen in Listing G. LISTING F: Straight subtraction of two TIMESTAMP datatypes. SELECT time. 1, time. FROM date_table. TIME1 TIME2 (TIME2- TIME1). LISTING G: Determine the interval breakdown between two dates for a TIMESTAMP datatype 1 SELECT time. FROM date_table. TIME1 TIME2 SECONDS MINUTES HOURS DAYS WEEKS. System Date and Time. In order to get the system date and time returned in a DATE datatype, you can use the SYSDATE function such as : SQL> SELECT SYSDATE FROM DUAL; In order to get the system date and time returned in a TIMESTAMP datatype, you can use the SYSTIMESTAMP function such as: SQL> SELECT SYSTIMESTAMP FROM DUAL; You can set the initialization parameter FIXED_DATE to return a constant value for what is returned from the SYSDATE function. This is a great tool for testing date and time sensitive code. Just beware that this parameter has no effect on the SYSTIMESTAMP function. This can be seen in Listing H. LISTING H: Setting FIXED_DATE and effects on SYSDATE and SYSTIMESTAMPSQL> ALTER SYSTEM SET fixed_date = '2. System altered. SQL> select sysdate from dual. SQL> select systimestamp from dual. JUL- 0. 3 1. 1. 0. AM - 0. 6: 0. 0. When working with date and time, the options are clear. You have at your disposal the DATE and TIMESTAMP datatypes. Just be aware, while there are similarities, there are also differences that could create havoc if you try to convert to the more powerful TIMESTAMP datatype. Each of the two has strengths in simplicity and granularity. Choose wisely.» See All Articles by Columnist. DBMS_SQLThe DBMS_SQL package provides an interface to use dynamic SQL to parse any data manipulation language (DML) or data definition language (DDL) statement using PL/SQL. For example, you can enter a DROPTABLE statement from within a stored procedure by using the PARSE procedure supplied with the DBMS_SQL package. Using DBMS_SQL Overview. Oracle lets you to write stored procedures and anonymous PL/SQL blocks that use dynamic SQL. Dynamic SQL statements are not embedded in your source program; rather, they are stored in character strings that are input to, or built by, the program at runtime.This enables you to create more general- purpose procedures.For example, dynamic SQL lets you create a procedure that operates on a table whose name is not known until runtime.Native Dynamic SQL is an alternative to DBMS_SQL that lets you place dynamic SQL statements directly into PL/SQL blocks.In most situations, Native Dynamic SQL is easier to use and performs better than DBMS_SQL. . However, Native Dynamic SQL itself has certain limitations: There is no support for so- called Method 4 (for dynamic SQL statements with an unknown number of inputs or outputs)There is no support for SQL statements larger than 3.K bytes. Also, there are some tasks that can only be performed using DBMS_SQL. The ability to use dynamic SQL from within stored procedures generally follows the model of the Oracle Call Interface (OCI). PL/SQL differs somewhat from other common programming languages, such as C. For example, addresses (also called pointers) are not user- visible in PL/SQL. As a result, there are some differences between the Oracle Call Interface and the DBMS_SQL package. These differences include the following: The OCI uses bind by address, while the DBMS_SQL package uses bind by value. With DBMS_SQL you must call VARIABLE_VALUE to retrieve the value of an OUT parameter for an anonymous block, and you must call COLUMN_VALUE after fetching rows to actually retrieve the values of the columns in the rows into your program. The current release of the DBMS_SQL package does not provide CANCEL cursor procedures. Indicator variables are not required, because NULLs are fully supported as values of a PL/SQL variable. A sample usage of the DBMS_SQL package follows. For users of the Oracle Call Interfaces, this code should seem fairly straightforward. Security Model. DBMS_SQL is compiled with AUTHIDCURRENT_USER. Any DBMS_SQL subprograms called from an anonymous PL/SQL block are run using the privileges of the current user. Constants. v. 6 constant INTEGER : = 0. INTEGER : = 1. v. Cracks Keygens And Serials Free . INTEGER : = 2. Types. General Types. Bulk SQL Types. BFILE_TABLE. TYPE bfile_table IS TABLE OF BFILE INDEX BY BINARY_INTEGER. BINARY_DOUBLE_TABLE. TYPE binary_double_table IS TABLE OF BINARY_DOUBLE INDEX BY BINARY_INTEGER. BINARY_FLOAT_TABLE. TYPE binary_float_table IS TABLE OF BINARY_FLOAT INDEX BY BINARY_INTEGER. TYPE blob_table IS TABLE OF BLOB INDEX BY BINARY_INTEGER. TYPE clob_table IS TABLE OF CLOB INDEX BY BINARY_INTEGER. IS TABLE OF DATE INDEX BY BINARY_INTEGER. INTERVAL_DAY_TO_SECOND_TABLE. TYPE interval_day_to_second_Table IS TABLE OF. INDEX BY binary_integer. INTERVAL_YEAR_TO_MONTH_TABLE. TYPE interval_year_to_month_table IS TABLE OF yminterval_unconstrained INDEX BY BINARY_INTEGER. DESC_REC, DESC_TAB. TYPE desc_rec IS RECORD (. BINARY_INTEGER : = 0. BINARY_INTEGER : = 0. VARCHAR2(3. 2) : = ''. BINARY_INTEGER : = 0. VARCHAR2(3. 2) : = ''. BINARY_INTEGER : = 0. BINARY_INTEGER : = 0. BINARY_INTEGER : = 0. BINARY_INTEGER : = 0. BINARY_INTEGER : = 0. BOOLEAN : = TRUE). TYPE desc_tab IS TABLE OF desc_rec INDEX BY BINARY_INTEGER. TYPE number_table IS TABLE OF NUMBER INDEX BY BINARY_INTEGER. TYPE time_table IS TABLE OF time_unconstrained INDEX BY BINARY_INTEGER. TIME_WITH_TIME_ZONE_TABLE. TYPE time_with_time_zone_table IS TABLE OF TIME_TZ_UNCONSTRAINED INDEX. BY BINARY_INTEGER. TIMESTAMP_TABLE. TYPE timestamp_table IS TABLE OF timestamp_unconstrained INDEX BY BINARY_INTEGER. TIMESTAMP_WITH_LTZ_TABLE. TYPE timestamp_with_ltz_table IS TABLE OF. TIMESTAMP_LTZ_UNCONSTRAINED INDEX BY binary_integer. TYPE urowid_table IS TABLE OF UROWID INDEX BY BINARY_INTEGER. TYPE varchar. 2_table IS TABLE OF VARCHAR2(2. INDEX BY BINARY_INTEGER. VARCHAR2. A, DESC_REC2. TYPE varchar. 2a IS TABLE OF VARCHAR2(3. INDEX BY BINARY_INTEGER. TYPE desc_rec. 2 IS RECORD (. TRUE). TYPE desc_tab. IS TABLE OF desc_rec. INDEX BY BINARY_INTEGER. TYPE varchar. 2s IS TABLE OF VARCHAR2(2. INDEX BY BINARY_INTEGER. EXCEPTION. pragma exception_init(inconsistent_type, - 6. This exception is raised by the COLUMN_VALUE Procedure or the VARIABLE_VALUE Procedures when the type of the given OUT parameter (for where to put the requested value) is different from the type of the value. Operational Notes. Execution Flow. OPEN_CURSORPARSEBIND_VARIABLE or BIND_ARRAYDEFINE_COLUMN, DEFINE_COLUMN_LONG, or DEFINE_ARRAYEXECUTEFETCH_ROWS or EXECUTE_AND_FETCHVARIABLE_VALUE, COLUMN_VALUE, or COLUMN_VALUE_LONGCLOSE_CURSOROPEN_CURSORTo process a SQL statement, you must have an open cursor. When you call the OPEN_CURSOR Function function, you receive a cursor ID number for the data structure representing a valid cursor maintained by Oracle. These cursors are distinct from cursors defined at the precompiler, OCI, or PL/SQL level, and are used only by the DBMS_SQL package. PARSEEvery SQL statement must be parsed by calling the PARSE Procedure. Parsing the statement checks the statement's syntax and associates it with the cursor in your program. You can parse any DML or DDL statement. DDL statements are run on the parse, which performs the implied commit. Note. When parsing a DDL statement to drop a package or a procedure, a deadlock can occur if you're still using a procedure in the package. After a call to a procedure, that procedure is considered to be in use until execution has returned to the user side. Any such deadlock timeouts after five minutes. The execution flow of DBMS_SQL is shown in Figure 1. BIND_VARIABLE or BIND_ARRAYMany DML statements require that data in your program be input to Oracle. When you define a SQL statement that contains input data to be supplied at runtime, you must use placeholders in the SQL statement to mark where data must be supplied. For each placeholder in the SQL statement, you must call one of the bind procedures, the BIND_ARRAY Procedures or the BIND_VARIABLE Procedures, to supply the value of a variable in your program (or the values of an array) to the placeholder. When the SQL statement is subsequently run, Oracle uses the data that your program has placed in the output and input, or bind, variables. DBMS_SQL can run a DML statement multiple times — each time with a different bind variable. The BIND_ARRAY procedure lets you bind a collection of scalars, each value of which is used as an input variable once for each EXECUTE. This is similar to the array interface supported by the OCI. DEFINE_COLUMN, DEFINE_COLUMN_LONG, or DEFINE_ARRAYThe columns of the row being selected in a SELECT statement are identified by their relative positions as they appear in the select list, from left to right. For a query, you must call one of the define procedures (DEFINE_COLUMN, DEFINE_COLUMN_LONG, or DEFINE_ARRAY) to specify the variables that are to receive the SELECT values, much the way an INTO clause does for a static query. Use the DEFINE_COLUMN_LONG procedure to define LONG columns, in the same way that DEFINE_COLUMN is used to define non- LONG columns. You must call DEFINE_COLUMN_LONG before using the COLUMN_VALUE_LONG procedure to fetch from the LONG column. Use the DEFINE_ARRAY procedure to define a PL/SQL collection into which you want to fetch rows in a single SELECT statement. DEFINE_ARRAY provides an interface to fetch multiple rows at one fetch. You must call DEFINE_ARRAY before using the COLUMN_VALUE procedure to fetch the rows. EXECUTECall the EXECUTE function to run your SQL statement. FETCH_ROWS or EXECUTE_AND_FETCHThe FETCH_ROWS function retrieves the rows that satisfy the query. Each successive fetch retrieves another set of rows, until the fetch is unable to retrieve anymore rows. Instead of calling EXECUTE and then FETCH_ROWS, you may find it more efficient to call EXECUTE_AND_FETCH if you are calling EXECUTE for a single execution. VARIABLE_VALUE, COLUMN_VALUE, or COLUMN_VALUE_LONGFor queries, call COLUMN_VALUE to determine the value of a column retrieved by the FETCH_ROWS call.
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