ABAP_ALTERNATIVES: 1 ... SET set_expression [WHERE sql_cond] 2 ... FROM wa 3 ... FROM TABLE itab
What does it do? The data in source defines which rows and columns are changed. Either individual columns are changed using the addition SET, or entire rows are overwritten using the addition FROM .
A wa data object that is not table-like or an itab internal table can be specified after FROM. The content of these objects determines which rows are changed and which values are used to overwrite the row(s). • SET UPDATE dbtab • WHERE UPDATE dbtab
ABAP Alternative 1 ... SET set_expression [WHEREsql_cond]
What does it do? After the SET adddition, the changes are specified in a list of change expressions in set_expression.
The addition WHERE uses a logical expression sql_cond to define in which rows of the database table the changes are executed. For the logical expression sql_cond, the same applies as for the WHERE condition of the statement SELECT, with the exception that no subqueries are to be evaluated in the database table to be changed. If no WHERE condition is specified, all the rows in the database table are changed.
The content of primary key fields can only be changed if the respective database table is not linked with a search help and if pool and cluster tables are not accessed. If these changes would create a row which would cause double entries in the primary key or a unique secondary index of the database table, then no rows are changed and sy-subrc is set to 4.
If the value of a column with type LRAW or LCHR is modified, the associated INT2 field must also be given a value.
Example ABAP Coding Dynamic conversion of the content of an arbitrary column in an arbitrary database table of a previous currency in Euro. PARAMETERS: table TYPE c LENGTH 30, column TYPE c LENGTH 30, old_curr TYPE sycurr.
DATA: set_expr TYPE string, condition TYPE string.
set_expr = column <(> <)><(> <)> ` = 'EUR'`.
condition = column <(> <)><(> <)> ` = old_curr`.
TRY. UPDATE (table) SET (set_expr) WHERE (condition). CATCH cx_sy_dynamic_osql_error. MESSAGE `Error in update!` TYPE 'I'. ENDTRY. • FROM UPDATE dbtab
ABAP Alternative 2 ... FROM wa
What does it do? If a non-table-like work area wa is specified, the system searches for a row in the database table which has the same content in its primary key as the corresponding beginning part of the work area. The work area must fulfill the prerequisites for use in Open SQL statements. If a work area which does not contain any reference variables for LOB handles is specified, the content of the work area is interpreted without being converted and follows the structure of the database table or the view. The content of the work area is assigned to the rows found. The assignment takes place without conversion, from left to right following the structure of the database table or the view. If a LOB handle structure is specified, it must be constructed (in accordance with the prerequisites) exactly like the structure of the database table. Work area components that are not LOB handle components are assigned directly to the corresponding column of the row found. In the case of a LOB handle component of a read stream type, this type is created. In this case of a type for a locator: this must exist and is used as a source. For details, see LOB handles.
If there is no row with the same content for the primary key in the database or if the change would lead to a double entry in a unique secondary index, the row is not changed and sy-subrc is set to 4.
By default, an automatic client handling is performed, which means that the client ID specified in wa is ignored and the current client is used instead. The content of wa is not affected. Automatic client handling can be switched off using the addition CLIENT SPECIFIED .
Latest notes:The work area wa should always be declared in relation to the database table or the view in the ABAP Dictionary. For the derivation of LOB handle structures, there are special additions to the statements TYPES and [CLASS-]DATA. If the database table or view is specified statically, a short form can be specified outside of classes. This means that the work area specified using FROM wa can be omitted. The prerequisite is that a table work area dbtab for the respective database table or the view is declared using the statement TABLES. The system expands the UPDATE statement implicitly to include the addition FROM dbtab.
Example ABAP Coding Change the discount rate of customer with customer number '00017777' (in the current client) to 3 per cent. DATA wa TYPE scustom.
SELECT SINGLE * FROM scustom INTO wa WHERE id = '00017777'.
wa-discount = '003'. UPDATE scustom FROM wa. • FROM TABLE UPDATE dbtab
ABAP Alternative 3 ... FROM TABLE itab
What does it do? If an internal table itab is specified, the system processes all the rows of the internal table in accordance with the rules for the work area wa, with the exception that when specifying an internal table, locators are used as a source but read streams cannot be created.
The row type of the internal table must fulfill theprerequisites for use in Open SQL statements.
If there is no row with the same content of theprimary key in the database (for a row of the internal table) or if the change would lead to a double entry in a unique secondary index, the row is not changed and sy-subrc is set to 4. If the internal table is empty, no rows are changed. However sy-subrc is still set to 0. The system field sy-dbcnt is set to the number of rows that are inserted.
Latest notes:When an internal table is used, package by package processing leads to a read access (running in parallel to an UPDATE on the same rows) that partially shows the new status and partially shows the old status.
Example ABAP Coding Reduction of the flight cost for all of today's flights of an airline carrier in the database table SFLIGHT by the percentage percent. The calculation of the new price is always carried out in an internal table sflight_tab and the database table is changed accordingly. PARAMETERS: p_carrid TYPE sflight-carrid, percent TYPE p LENGTH 1 DECIMALS 0.
DATA sflight_tab TYPE TABLE OF sflight. FIELD-SYMBOLS <(><<)>sflight> TYPE sflight.
SELECT * FROM sflight INTO TABLE sflight_tab WHERE carrid = p_carrid AND fldate = sy-datum.
