Difference between revisions of "SYSCOLUMNS"
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==Purpose== | ==Purpose== | ||
Description of the table columns available in the catalog | Description of the table columns available in the catalog | ||
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==See Also== | ==See Also== | ||
[[SQL Data Types|DATA TYPES]], [[SQL SELECT|SELECT]], [[SQL System Tables|SYSTEM TABLES]] | [[SQL Data Types|DATA TYPES]], [[SQL SELECT|SELECT]], [[SQL System Tables|SYSTEM TABLES]] | ||
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==Description== | ==Description== | ||
System Tables are system defined read-only tables. You can query these tables using the SELECT statement. | System Tables are system defined read-only tables. You can query these tables using the SELECT statement. | ||
− | + | {| class="wikitable" width="100%" | |
− | {| class="wikitable" | + | |
!Column||Data Type||Width||Description | !Column||Data Type||Width||Description | ||
|- | |- | ||
Line 24: | Line 21: | ||
|DATA_TYPE||N||2||SQL data type | |DATA_TYPE||N||2||SQL data type | ||
|- | |- | ||
− | |TYPE_NAME||C||30||Data source dependent type name | + | |valign="top"|TYPE_NAME||valign="top"|C||valign="top"|30||Data source dependent type name |
|- | |- | ||
|COLUMN_SIZE||N||3||Precision | |COLUMN_SIZE||N||3||Precision | ||
Line 44: | Line 41: | ||
|SQL_DATETIME_SUB||N||1||Reserved | |SQL_DATETIME_SUB||N||1||Reserved | ||
|- | |- | ||
− | |CHAR_OCTET_LENGTH||N||1||For char types the maximum number of bytes in the column | + | |valign="top"|CHAR_OCTET_LENGTH||valign="top"|N||valign="top"|1||For char types the maximum number of bytes in the column |
|- | |- | ||
− | |ORDINAL_POSITION||N||4||Index of column in table (starting at 1) | + | |valign="top"|ORDINAL_POSITION||valign="top"|N||valign="top"|4||Index of column in table (starting at 1) |
|- | |- | ||
− | |IS_NULLABLE||C||3||"NO" means column definitely does not allow NULL values; "YES" means the column might allow NULL values. An empty string means unknown. | + | |valign="top"|IS_NULLABLE||valign="top"|C||valign="top"|3||"NO" means column definitely does not allow NULL values; "YES" means the column might allow NULL values. An empty string means unknown. |
|- | |- | ||
|} | |} | ||
+ | Return values for Lianja field types are shown in the table below. | ||
+ | |||
+ | {| class="wikitable" width="100%" | ||
+ | !Field Type||TYPE_NAME||DATA_TYPE | ||
+ | |- | ||
+ | |Character||CHAR||1 | ||
+ | |- | ||
+ | |Numeric||NUMERIC||2 | ||
+ | |- | ||
+ | |Logical||BOOLEAN||-7 | ||
+ | |- | ||
+ | |Varchar||LONG VARCHAR||-4 | ||
+ | |- | ||
+ | |Blob||LONG VARBINARY||-4 | ||
+ | |- | ||
+ | |Currency||CURRENCY||0 | ||
+ | |- | ||
+ | |Date||DATE||91 | ||
+ | |- | ||
+ | |Datetime||DATETIME||93 | ||
+ | |- | ||
+ | |Int||INTEGER||2 | ||
+ | |- | ||
+ | |Float||FLOAT||8 | ||
+ | |- | ||
+ | |Short||SHORT||5 | ||
+ | |- | ||
+ | |Real||REAL||7 | ||
+ | |- | ||
+ | |Json||LONG VARCHAR||-4 | ||
+ | |- | ||
+ | |} | ||
==Example== | ==Example== | ||
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</code> | </code> | ||
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[[Category:Documentation]] | [[Category:Documentation]] | ||
[[Category:SQL]] | [[Category:SQL]] | ||
[[Category:System Tables]] | [[Category:System Tables]] |
Latest revision as of 13:21, 6 December 2021
Contents
Purpose
Description of the table columns available in the catalog
See Also
DATA TYPES, SELECT, SYSTEM TABLES
Description
System Tables are system defined read-only tables. You can query these tables using the SELECT statement.
Column | Data Type | Width | Description |
---|---|---|---|
TABLE_CAT | C | 30 | Table catalog |
TABLE_SCHEM | C | 30 | Table schema |
TABLE_NAME | C | 30 | Table name |
COLUMN_NAME | C | 25 | Column name |
DATA_TYPE | N | 2 | SQL data type |
TYPE_NAME | C | 30 | Data source dependent type name |
COLUMN_SIZE | N | 3 | Precision |
BUFFER_LENGTH | L | 1 | Reserved |
DECIMAL_DIGITS | N | 2 | Scale |
NUM_PREC_RADIX | N | 2 | Radix (typically either 10 or 2) |
NULLABLE | N | 2 | Is NULL allowed? |
REMARKS | C | 25 | Comment describing column |
COLUMN_DEF | C | 30 | Default value |
SQL_DATA_TYPE | N | 1 | Reserved |
SQL_DATETIME_SUB | N | 1 | Reserved |
CHAR_OCTET_LENGTH | N | 1 | For char types the maximum number of bytes in the column |
ORDINAL_POSITION | N | 4 | Index of column in table (starting at 1) |
IS_NULLABLE | C | 3 | "NO" means column definitely does not allow NULL values; "YES" means the column might allow NULL values. An empty string means unknown. |
Return values for Lianja field types are shown in the table below.
Field Type | TYPE_NAME | DATA_TYPE |
---|---|---|
Character | CHAR | 1 |
Numeric | NUMERIC | 2 |
Logical | BOOLEAN | -7 |
Varchar | LONG VARCHAR | -4 |
Blob | LONG VARBINARY | -4 |
Currency | CURRENCY | 0 |
Date | DATE | 91 |
Datetime | DATETIME | 93 |
Int | INTEGER | 2 |
Float | FLOAT | 8 |
Short | SHORT | 5 |
Real | REAL | 7 |
Json | LONG VARCHAR | -4 |
Example
SELECT * FROM syscolumns; WHERE type_name = 'DATETIME'