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Oracle SQL Plus The Definitive Guide- P23 doc

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< previous page page_191 next page > < previous page page_192 next page > Page 192 Table 6-9. Columns in the ALL_TRIGGER_COLS View (continued) TABLE_OWNER The owner of the table on which the trigger is defined. Usually this is the same as the trigger owner, but it doesn't have to be. TABLE_NAME The name of the table on which the trigger is defined. COLUMN_NAME The name of a column in the table that is used within the trigger, either within the trigger's specification, or within the PL/SQL block executed by the trigger. COLUMN_LIST Either YES or NO, depending on whether or not the firing of the trigger is dependent on this column being updated. This is only applicable to UPDATE triggers. A value of YES indicates that the column forms part of the column list following the keyword UPDATE in the CREATE TRIGGER statement. COLUMN_USAGE This tells you how the column is used within the trigger. It will contain some combination of the following strings, separated by one space:NEW: The new version of the column is referenced. OLD: The old version of the column is referenced. IN: The column is referenced, but not updated. OUT: The column's value is set, but never read. IN OUT: The column's value is both referenced and updated. For example, a value of NEW IN OUT tells you that the trigger both sets the value of the column (OUT) and reads the value of te column (IN). It also tells you that it is the new version (NEW) of the column that is used. The ALL_SYNONYMS view The ALL_SYNONYMS view returns one row for each synonym you own and one for each public synonym. Table 6-10 describes the columns in this view. Table 6-10. Columns in the ALL_SYNONYMS View Column Contents OWNER The owner of the synonym. The owner name will be PUBLIC for public synonyms, which are accessibe by all detabase users. SYNONYM_NAME The name of the synonym. TABLE_OWNER The name of the table's owner. TABLE_NAME The table name to which the synonym points. DB_LINK If the synonym points to a table in another database instance, this is the database link name that points to that instance. The ALL_TAB_PRIVS view The ALL_TAB_PRIVS view shows privileges granted to others on objects you own. It also shows privileges granted to you on objects owned by others. Table 6-11 describes this view. < previous page page_192 next page > < previous page page_193 next page > Page 193 Table 611. Columns in the ALL_TAB_PRIVS View Column Contents GRANTOR The username of the person who granted the privilege. GRANTEE The username or rolename to which access was granted. TABLE_SCHEMA The owner of the object. TABLE_NAME The object's name. PRIVILEGE The privilege that was granted on the object (e.g., INSERT or DELETE). GRANTABLE This will be either YES or NO, depending on whether or not the privilege was granted with the administrative option. The ALL_COL_PRIVS view This view only comes into play when you have granted UPDATE privileges to a user, and when you have limited those update privileges to a specific set of columns. This view returns that list of updateable columns, and is described in Table 612. Table 612. Columns in the ALL_COL_PRIVS_MADE View Column Contents GRANTOR The username of the person who granted the privilege. GRANTEE The username or rolename to which access was granted. TABLE_SCHEMA The owner of the object. TABLE_NAME The object's name. COLUMN_NAME The column name on which the privilege was granted. PRIVILEGE The privilege that was granted on the object (e.g., INSERT or DELETE). GRANTABLE This will be either YES or NO, depending on whether or not the privilege was granted with the administrative option. Tables When it comes to looking at a table and its column definitions, there are two data dictionary views you need to be concerned with. These views are: ALL_TABLES ALL_TAB_COLUMNS The ALL_TABLES view contains one row for each table. You can use this view to get a quick list of tables you own or to which you have been granted some type of access. ALL_TABLES has a one-to-many relationship to ALL_TAB_COLUMNS, which contains one record for each column in a table. ALL_TAB_COLUMNS is the source for information on column names, datatypes, default values, and so forth. < previous page page_193 next page > < previous page page_194 next page > Page 194 Listing Tables You Own To get a quick list of tables you own, it's easier to use the USER_TABLES view than ALL_TABLES. Remember, USER_TABLES shows you only the tables you own. To see a list of your tables, simply select the table_name column. SQL> SELECT table_name FROM user_tables; TABLE_NAME DATA_TYPE_TEST DT_TEST EMPLOYEE PROJECT PROJECT_HOURS 5 rows selected. To see tables owned by other users, you need to query the ALL_TABLES view. Just be sure to qualify your query by specifying the owner's username in the WHERE clause. Here's an example that lists all tables owned by the user SYSTEM: SELECT table_name FROM all_tables WHERE owner = SYSTEM; You can make things easy on yourself by writing a script to list tables. The following listing shows one approach you can take. It prompts you for a username, then lists all tables owned by that user. The table listing is in alphabetical order. DESCRIPTION List tables owned by the current user, or owned by a specified user. The user is prompted for an owner name. If an owner is not specified, i.e. the user just presses ENTER, then tables are listed for the current user. SET ECHO OFF SET FEEDBACK OFF SET VERIFY OFF SET DEFINE ON SET HEADING OFF Ask the user for the owner. ACCEPT username CHAR PROMPT List tables for user: PROMPT Set up the title to print the owner. TTITLE LEFT TABLES OWNED BY: owner SKIP 1 COLUMN owner NOPRINT NEW_VALUE owner List the tables. SELECT DECODE(&&username,NULL,USER,UPPER(&&username)) owner, indent, < previous page page_194 next page > < previous page page_195 next page > Page 195 table_name FROM all_tables WHERE owner = DECODE(&&username,NULL,USER,UPPER(&&username)) ORDER BY table_name; Clean up: undefine vars, clear columns, change settings back to defaults. UNDEFINE username UNDEFINE owner COLUMN owner CLEAR TTITLE OFF SET HEADING ON SET FEEDBACK ON SET VERIFY ON When you run this script, it will prompt you for a username. Then it will list all the tables owned by that user. Here's an example: SQL> @list_tables List tables for user: jeff TABLES OWNED BY: jeff EMPLOYEE MY_TABLE PROJECT PROJECT_HOURS As you can see, the resulting list shows all the tables owned by the user named JEFF. The DECODE function in the SELECT statement translates any username you enter to uppercase. If you were to press ENTER at the username prompt, that same DECODE statement would translate your empty response to your username, so you would see your tables. Listing Column Definitions for a Table To list the columns in a table, you will almost certainly want to write a script. The script shown next offers one possible approach to doing this. Some of the expressions, particularly the ones that call the DECODE function, get a bit complicated. I'll explain those after the listing. The LIST_COLUMNS.SQL script DESCRIPTION List all the columns for a table, together with their datatypes, default values, and nullability. INPUTS Param 1 A table name, optionally qualified optionally qualified by an owner name. For example: "SYS.ALL_TAB_COLUMNS". SET ECHO OFF SET VERIFY OFF < previous page page_195 next page > < previous page page_196 next page > Page 196 SET FEEDBACK OFF SET RECSEP OFF SET HEADING ON SET PAGESIZE 9999 SET LONG 1000 SET LINESIZE 80 CLEAR COLUMNS CLEAR BREAKS TTITLE OFF BTITLE OFF Dissect the input argument, and get the owner name and table name into two seperate substitution variables. The owner name defaults to the current user. DEFINE s_owner_name = DEFINE s_table_name = COLUMN owner_name NOPRINT NEW_VALUE s_owner_name COLUMN table_name NOPRINT NEW_VALUE s_table_name SELECT DECODE(INSTR(&&1,.), 0,USER, /*Default to current user.* UPPER(SUBSTR(&&1,1,INSTR(&&1,.)-1))) owne DECODE(INSTR(&&1,.), 0,UPPER(&&1), /*Only the table name was passed in.*/ UPPER(SUBSTR(&&1,INSTR(&&1,.)+1))) table_name FROM dual; Set up the page title, force just one page break by breaking on the table name column. TTITLE LEFT - COLUMN LISTING FOR s_owner_name . s_table_name - SKIP 2 BREAK ON table_name SKIP PAGE Set up the formats and widths for the columns to be displayed. COLUMN column_id NOPRINT COLUMN table_name NOPRINT COLUMN column_name FORMAT A30 HEADING Column Name COLUMN data_type FORMAT A17 HEADING Data Type COLUMN not_null FORMAT A9 HEADING Nullable? SELECT table_name, column_id, column_name, DECODE (data_type, VARCHAR2 , VARCHAR2 ( ¦¦ TO_CHAR(data_length) ¦¦ ), NVARCHAR2,NVARCHAR2 ( ¦¦ TO_CHAR(data_length) ¦¦ ), CHAR,CHAR ( ¦¦ TO_CHAR(data_length) ¦¦ ), NCHAR,NCHAR ( ¦¦ TO_CHAR(data_length) ¦¦ ), NUMBER, DECODE (data_precision, NULL, NUMBER, NUMBER ( ¦¦ TO_CHAR(data_precision) ¦¦ , ¦¦ TO_CHAR(data_scale) ¦¦ )), < previous page page_196 next page > < previous page page_197 next page > Page 197 FLOAT, DECODE (data_precision, NULL, FLOAT, FLOAT ( ¦¦ TO_CHAR(data_precision) ¦¦ )), DATE,DATE, LONG,LONG, LONG RAW,LONG RAW, RAW,RAW ( ¦ ¦ TO_CHAR(data_length) ¦¦ ), MLSLABEL,MLSLABEL, ROWID,ROWID, CLOB,CLOB, NCLOB,NCLOB, BLOB,BLOB, BFILE,BFILE, data_type ¦¦ ???) data_type, DECODE (nullable, N,NOT NULL) not_null FROM all_tab_columns WHERE table_name = &&s_table_name AND owner = &&s_owner_name ORDER BY column_id; Now list any columns with default values defined. This is done as a separate select because SQL*Plus versions 8.0.3 and 8.0.4 do not handle null LONG columns properly. TTITLE SKIP 2 LEFT - DEFAULT VALUES FOR s_owner_name . s_table_name - SKIP 2 COLUMN default_value HEADING Default Value FORMAT A40 WORD_WRAPPED SELECT table_name, column_name, data_default default_value FROM all_tab_columns WHERE table_name = &&s_table_name AND owner = &&s_owner_name AND data_default IS NOT NULL ORDER BY column_id; Clean up by undefining variables, clearing break and column definitions, and changing all settings back to their defaults. UNDEFINE s_owner_name UNDEFINE s_table_name CLEAR BREAKS CLEAR COLUMNS TTITLE OFF SET ECHO OFF SET VERIFY ON SET FEEDBACK ON SET RECSEP WRAPPED SET HEADING ON < previous page page_197 next page > . have to be. TABLE_NAME The name of the table on which the trigger is defined. COLUMN_NAME The name of a column in the table that is used within the trigger, either within the trigger's specification,. users. SYNONYM_NAME The name of the synonym. TABLE_OWNER The name of the table's owner. TABLE_NAME The table name to which the synonym points. DB_LINK If the synonym points to a table in another database. trigger's specification, or within the PL /SQL block executed by the trigger. COLUMN_LIST Either YES or NO, depending on whether or not the firing of the trigger is dependent on this column

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